Dec 04

Chevy Volt’s Coefficient of Drag is 0.28, Beats Prius and Insight

 

2011 Chevrolet Volt in the wind tunnel at the Aerodynamic Labora

[ad#post_ad]GM has talked tirelessly abut how aerodynamic the Volt is, how its shape was born from the wind tunnel, and how important aerodynamics are for the car to achieve its 40 miles all electric range.

Yet for all that talk, the company has never released any official figure for the vehicle’s coefficient of drag (CD). This is the numerical measurement that indicates how slippery a car is, and unlikely to be slowed by wind resistance.

Bob Boniface who is chief of Voltec design finally provided us the details that were obtained when GM measured the Volt and its competitors on its own wind tunnel.

“We had the comparably-equipped 2010 Prius with 17 inch wheels, and the new Insight,” he said.

“The Prius came in at .30,” said Boniface. “That was a number that was verified in our tunnel, in Chrysler’s tunnel, and in Ford’s tunnel.”

“The Insight was 0.32, and the Volt was .28,” he said.

“I’d like to test the Volt in the same tunnel where Toyota got their 0.25 value,” he teased.

He expanded:

This number is for the Volt IVer which is representative of our production car. We were resistant to give out the number earlier for two reasons. One we wanted to wait until we tested our IVer. Also, we didn’t want to report it out until we saw where the competition was because we know that those numbers depend on how the tunnels are calibrated.

If I quoted 0.28 a year ago people would have said ‘aha’ the competition got 0.25. But its really all relative to what tunnel it was tested on.

The base Prius with the smaller wheels may come in lower, but we don’t offer 15 inch wheels.

EV-1
According to GM’s aerodynamics engineer Nina Tortosa, the old method of testing yielded .19, but with current testing methodology it would equate to .21.

“But that vehicle didn’t have a rollover and frontal impact structure of today’s standards,” said Boniface. “You could not sell that car today. That’s not to say we wont get to .21 again with another car. We always try to get drag down but we have to protect our styling flexibility.”

Corvette
The current base Corvette is the most slippery and its a 0.29, slightly less aerodynamic than the Volt.

This entry was posted on Friday, December 4th, 2009 at 7:23 am and is filed under Design, Efficiency. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

COMMENTS: 153


  1. 1
    loboc

     

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    Dec 4th, 2009 (7:36 am)

    I’d rather have some style and room inside than a maxed-out CD number.

    At most commuter speeds (I regularly go less than 30mph when commuting) the electric traction and regen braking are more important to me.

    That said, it would be cool to have a retro EV1 body :)


  2. 2
    Dave G

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    Dec 4th, 2009 (7:38 am)

    As a point of reference, the Aptera 2e comes in with a coefficient of drag at .15
    http://www.aptera.com/love.php


  3. 3
    Herm

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    Dec 4th, 2009 (7:41 am)

    loboc: At most commuter speeds (I regularly go less than 30mph when commuting) the electric traction and regen braking are more important to me.

    You are going to get great EV range out of the Volt, speed kills (your mileage).


  4. 4
    JEC

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    Dec 4th, 2009 (7:42 am)

    I measured my self. I got a 0.14!

    Good news. I would have guessed a cd closer to the civic, so this is actually very impressive, based on the styling.


  5. 5
    loboc

     

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    Dec 4th, 2009 (7:50 am)

    They can do better:
    http://www.electrifyingtimes.com/gmprecept.html

    The Dodge Intrepid (I have one!) is very good as well.
    http://en.wikipedia.org/wiki/Automobile_drag_coefficient


  6. 6
    Right Lane Cruiser

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    Dec 4th, 2009 (8:03 am)

    You’ll find my Insight is pretty far down on the CoD scale as well, but the real determining factor is the actual drag… which is proportional to the surface area presented perpendicular to direction of travel (CoD multiplied by area). For example, the Prius and my (2002) Insight are both listed at .25 but it takes less energy to move my car because it has less frontal area.

    So, the pertinent question is, “How does the actual aerodynamic drag of the Volt compare to that of the Prius and the Insight?”

    And affirmative to the “speed kills mileage” comment. ;)


  7. 7
    Dan Petit

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    Dec 4th, 2009 (8:08 am)

    That’s extremely true and widespread, that different test equipment is calibrated VERY differently and the software to process the imputs also varies so very widely also.

    That’s just for CD. And, the use of the same test equipment is critical for comparative testing. In the shop, it relates to before and after each (of about 25) diagnostic procedural step(s) to use the same test equipment.

    Although in a wind tunnel, you have, for example, a controlled situation such as air temperature (a critical covariable for the software). But in a diagnostic situation, the best that can be done is to have the vehicle cooled down overnight in the service bay before beginning a sequence of trained observations at service-bay ambient temperature the next moring.

    It really is exciting to be allowed to be part of this GM process. It really makes you feel like the technical people want to be your “tech friends”.


  8. 8
    George S. Bower

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    Dec 4th, 2009 (8:12 am)

    This lower drag coefficient, combined with the Volt’s lower frontal area (it’s the product of the 2 that give road horsepower required) give the volt a 10%+ advantage over the Prius in the CS MPG department. This lower road power requirement should more than compensate for the lower energy conversion efficiency of the Volt in the ICE, CS mode(series vs parallel). So, theoretically, the Volt should acheve Prius mileage in CS mode. If they don’t, something serious went wrong.


  9. 9
    Nelson

     

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    Dec 4th, 2009 (8:14 am)

    Does the mass of a car have any bearing on its COD measurement?
    If you took the Volt and filled it with bricks would the measured COD be the same?

    I’d like to know how the COD is measured. Anyone have an informative link?

    NPNS!


  10. 10
    carcus1

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    Dec 4th, 2009 (8:20 am)

    Does the mass of a car have any bearing on its COD measurement?
    No.
    If you took the Volt and filled it with bricks would the measured COD be the same?
    Yes. (unless you want to get overly technical: i.e. car squatting down, pitched, etc)
    I’d like to know how the COD is measured. Anyone have an informative link?
    http://en.wikipedia.org/wiki/Drag_coefficient

    /”COD” is Cash On Delivery. “Cd” is Drag Coefficient


  11. 11
    Dr. Ibringdoh

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    Dec 4th, 2009 (8:26 am)

    Nelson: Does the mass of a car have any bearing on its COD measurement?If you took the Volt and filled it with bricks would the measured COD be the same?I’d like to know how the COD is measured. Anyone have an informative link?NPNS!  (Quote)

    Nelson,

    In the equation for drag coefficient, the density of the fluid or medium counts (in this case, air), but not the density of the object:

    Cd = Fd/(1/2*p*v^2*A) where:

    Cd is coefficient of drag
    Fd is Force of drag
    p (more properly, the Greek letter rho) is density of the fluid (air)
    v is velocity of the object
    A is area of the object

    http://en.wikipedia.org/wiki/Drag_coefficient

    Looking at the design of the vehicles, there are some subtle differences between the Volt and the Prius which may contribute to a reduced drag, just as there are subtle differences between the Prius and the Insight which appear to accomplish the same.

    It would certainly be interesting to view the results of an independent wind tunnel, such as in San Diego, CA.

    Respectfully,

    Dr. Ibringdoh


  12. 12
    ardvark

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    Dec 4th, 2009 (8:30 am)

    WSJ is reporting that Bob Lutz has been removed as gm’s director of marketing. Whitacre wants shift to younger people.


  13. 13
    carcus1

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    Dec 4th, 2009 (8:35 am)

    As others have mentioned, Cd is only part of the the equation. . . with Area (A) being the other key ingredient for the purposes of vehicle comparision. A design could have a great Cd, but if it’s got a huge frontal area, then the drag force will be high with corresponding consequences to the mpg.

    / sort of a cheap trick (imo) to negate the wheel size in the volt vs prius comparison. It’s all (including wheel size) part of the total engineering design.

    perhaps a better link here (wiki’s got it all, I guess), simplified, automotive specific, but less info:
    http://en.wikipedia.org/wiki/Automobile_drag_coefficient


  14. 14
    joe

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    Dec 4th, 2009 (8:42 am)

    “The Prius came in at .30,” said Boniface. “That was a number that was verified in our tunnel, in Chrysler’s tunnel, and in Ford’s tunnel.”

    “The Insight was 0.32, and the Volt was .28,” he said.

    “I’d like to test the Volt in the same tunnel where Toyota
    got their 0.25 value,” he teased.”

    ***************************************************************

    Toyota and Honda are not companies of integrity like most people think. They will snow the general public to make you think they are smarter.
    Now, that the domestic car makers are fully awake, we will see who is smarter.

    Go GM and Ford go!! As with Chrysler it may be a little too late, but I do hope they can be successful, again!


  15. 15
    carcus1

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    Dec 4th, 2009 (8:43 am)

    (click to show comment)


  16. 16
    Nuclearboy

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    Dec 4th, 2009 (8:43 am)

    For what its worth…

    The aerodynamic drag refers to the power wasted when you have to accellerate the air in front of you up to the speed of the car as the car pushes through it. The still air pushed forward (think of a fan and the power needed to push the air).

    If you have a car with a 2 square meter frontal area, you don’t really have to push the equivalent of 2 square meters of air surface forward. Some of the air moves out of the way as you pass by. The drag coefficient tells you the fraction of air (equivalent) that cannot get out of the way as you go by.

    If the drag coefficient is 0.5, then you must push an equivalent air stream forward with an area equal to 0.5 * the area of your car. If you make edges smooth or tapered in certain ways, more air can slip around the car and the drag coefficient goes down.

    What really matters is the total amount of air that you must push forward (ie. waste power on as you accellerate the air up to your speed). This total amount of air is the combination of Cd * Area.

    So, you can reduce your aerodynamic drag by reducing Frontal Area or the Cd.

    Its also good to point of that drag force is proportional to the air density multiplied by the Velocity squared. So, doubling your velocity increases the drag force by four times. Speeding really kills your gas mileage due to this aerodynamic load.


  17. 17
    JonP.

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    Dec 4th, 2009 (8:44 am)

    I hope this guy Whitacre knows what he’s doing. Looks like he’s making alot of personell changes in a short time frame.

    http://online.wsj.com/article/SB10001424052748704007804574575480594243994.html?mod=WSJ_hpp_MIDDLTopStories

    Lutz is going back to design!


  18. 18
    Jim I

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    Dec 4th, 2009 (8:47 am)

    It is the very last sentence that I find the most interesting:

    “The current base Corvette is the most slippery and its a 0.29, slightly less aerodynamic than the Volt.”

    So lets make a Voltec Mini ‘Vette!! It is fiberglass, so it is saving weight. It should be a smaller version, so as not to compete directly with or hurt the mystique of an ICE based Corvette. It would have great torque. I am thinking about the size of a Solstice. And as a two seater, that same 16 KW/Hr battery pack should actually get a better AER.

    It would make us sports car types very happy!!

    If I have to wait another two or three years, I might as well get what I really want………………….


  19. 19
    Kevin R

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    Dec 4th, 2009 (8:58 am)

    I would give up some mileage to have the original design concept as a possibility. It will never be but its nice to dream of a possibility in the future when battery pack prices and density increase enough. It was such a powerful looking car.

    That being said, I’m buying this Volt.


  20. 20
    Neutron Flux

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    Dec 4th, 2009 (9:07 am)

    Dave G: As a point of reference, the Aptera 2e comes in with a coefficient of drag at .15http://www.aptera.com/love.php  (Quote)

    Thats nice but that car recently back to the drawing board for an almost complete redesign to improve structural integrity etc. Not sure it will be on the street before the Volt, in production mode I heard they are waiting on those ultra capacitors from that unnamed company (LOL). OK for commuter car but won’t work for families with seating for 2. Nice if you can afford a limited use vehicle. Entry / exit still looks a bit difficult even after redesigning. I’d suggest trying before buying.


  21. 21
    Herm

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    Dec 4th, 2009 (9:09 am)

    carcus1: Feds got rid of the wrong guy. The only real winner that Lutz has been involved in was the initial development of the original Explorer. He is responsible for big ticket, low sales units – i.e. Viper, Prowler, Enclave, etc.

    and the Volt


  22. 22
    Herm

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    Dec 4th, 2009 (9:17 am)

    “The base Prius with the smaller wheels may come in lower, but we don’t offer 15 inch wheels.”

    They should compare the base version of both cars, otherwise GM should put an asterisc behind the claim.


  23. 23
    Kyle

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    Dec 4th, 2009 (9:26 am)

    Dave G: As a point of reference, the Aptera 2e comes in with a coefficient of drag at .15
    http://www.aptera.com/love.php  

    Yes the Aptera 2e has a low coefficient of drag but Aptera will be lucky if it ever gets any of it’s 2es into home garages. Let us not forget that Aptera is on the verge of insolvency. Also, we need to keep in mind some facts about the auto industry. Of the thousands of car companies that have tried to develop cars over the industries 110+ years the vast majority have perished quickly. The odds of success are low in any industry but extremely low in the auto industry which is characterized by extreme capital and intellectual intensiveness, long lead times, extremely complicated supply chains, relatively low margins, and currently still much over capacity. In ten years Aptera, Tesla and the likes will most likely be gone. So its interesting that the 2e achieved a .15 cd but they did it with carbon fiber that is still not even close to being competitive with metal stamping techniques in terms of rate of production and ultimately cost. GM and the other majors don’t choose carbon fiber for large run vehicles because they are stuck in their ways its because these techniques are still not viable for large production runs. Aptera is a design study no more.


  24. 24
    Van

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    Dec 4th, 2009 (9:30 am)

    Herm @ 22 you beat me to it. My question was, what is the Prius number using standard wheels, and what is the Volt number using 17″ wheels.

    And a big +1 to Nuclear Boy @ 16 for explaining the difference between drag and coefficient of drag (cd). And one more thing, when reading about how dimples might lower drag, some talked of basic drag and parasitic drag. The dimples were supposed to allow better air to flow into the void behind the car, thus reducing the “differential” pressure and improve efficiency at high speed. Any validity to that?


  25. 25
    kdawg

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    Dec 4th, 2009 (9:48 am)

    #15 carcus1 said “He is responsible for big ticket, low sales units – i.e. Viper, Prowler, Enclave, etc.”

    —————

    The Buick Enclave is one of GM’s most popular cars?


  26. 26
    nasaman

     

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    Dec 4th, 2009 (9:49 am)

    In other news, production of the Opel Ampera for left-hand-drive European markets is slated to start in late 2011. “Everything has gone according to plan,” said Gherardo Corsini, GM’s director for European electric vehicle implementation, according to a report today by the online subscription service Just-Auto.com.

    Hooray! My hope of buying an Ampera in Europe, touring the continent in it, then shipping this gorgeous, distinctively-styled sister to the Volt to a port in my home state of Florida may be back on track!


  27. 27
    kdawg

     

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    Dec 4th, 2009 (9:53 am)

    Lyle – see if you can get the Cd of the Converj.


  28. 28
    Jason M. Hendler

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    Dec 4th, 2009 (9:55 am)

    … so the Prius didn’t have to look like that.

    I’ve said it before and I will say it again, Toyota left money on the table with the styling of the Prius. I can’t imagine how enormous Prius sales would be today, if only they had provided better styling.


  29. 29
    nasaman

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    Dec 4th, 2009 (10:04 am)

    Jason M. Hendler: … so the Prius didn’t have to look like that.I’ve said it before and I will say it again, Toyota left money on the table with the styling of the Prius. I can’t imagine how enormous Prius sales would be today, if only they had provided better styling.  (Quote)

    I agree, Jason! ….And I also wonder how well the Ampera will do in Europe as a result of its highly-distinctive front-end styling (which is MUCH more to my taste than the Volt’s rather plain vanilla front-end).


  30. 30
    MuddyRoverRob

     

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    Dec 4th, 2009 (10:05 am)

    Herm: “The base Prius with the smaller wheels may come in lower, but we don’t offer 15 inch wheels.”They should compare the base version of both cars, otherwise GM should put an asterisc behind the claim.  (Quote)

    I for one don’t care what the base tiny unsafe tire size returns.

    I get the best tires available on whatever car I buy. Although smaller tires might give a slight improvement in straight line fuel economy once you try to do ‘extreme car stuff’ like turning or stopping those small patches of rubber show their weaknesses.

    I only buy the ‘loaded’ model with the larger tires (like most people do) so these numbers using the larger tires are more realistic.


  31. 31
    stuart22

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    Dec 4th, 2009 (10:09 am)

    Whoop-di-do. These numbers mean little to the average consumer, whose interest in numbers is focused upon cost of operation (MPG) and performance when judging a car.

    Sure, they’re fun to talk about, but it pretty much ends up being a pissing contest between car makers for bragging rights.


  32. 32
    Loboc

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    Dec 4th, 2009 (10:11 am)

    Jim I: So lets make a Voltec Mini ‘Vette!! It is fiberglass, so it is saving weight.

    A Corvette weighs just as much as any other car. More than some exotics.

    Fiberglass itself is not necessarily lighter than steel. You need more frame to support it as fiberglass is a poor structural material.

    If you look at a wrecked ‘Vette or boat, the story will be clear. Fiberglass shatters and cracks on impact. If you put holes in it (like for windows and door handles and things), it weakens the structure.

    Now if you use reinforced/modified fiberglass (such as carbon fiber), you can achieve good weight vs structure. But, it is VERY expensive.


  33. 33
    Dave K.

     

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    Dec 4th, 2009 (10:35 am)

    What is puzzling is seeing the parade of basic car designs come out year after year. The early 70′s Subaru DL has more styling than half of the new cars on the road. Or the Mazda RX models. How bout’ the Ford Torino?

    torino%20prius%20comparison.jpg

    What’s up with this?

    =D~


  34. 34
    mikeinatl.

     

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    Dec 4th, 2009 (10:38 am)

    That’s a cool photo. Is it real or PhotoShop?
    Either way, makes the VOLT look mighty slippery.

    I’m not sure we have seen that color before.
    And, off the thread, but are there photos of the VOLT in its new contest-winning colors?


  35. 35
    carcus1

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    Dec 4th, 2009 (10:44 am)

    kdawg: carcus

    From April, 2008:

    “Enclave buyers belong to a highly coveted pool, sporting an average age of 53 and median annual household incomes of $130k. By appealing to high earners, the Enclave generates substantially higher revenues than its fellow Lambda triplets. J.D. Power reports recent average transaction prices of $38,479, $3500 greater than the mid-tier GMC Acadia and more than $5600 above the Saturn Outlook. Thanks to Enclave’s sales performance, Buick’s overall transaction prices increased 16.1 percent over the year, substantially outperforming the industry average of 0.6 percent.

    The actual sales figures, however, are less inspiring. At its current sales pace of about 45 – 50k units per year, Enclave deliveries lag behind such rivals as Lexus RX and Ford Edge, as well as its badge-engineered brother, the GMC Acadia. Those hoping for a Lambda-based home run will need to find another ballpark.”

    http://www.thetruthaboutcars.com/gm-death-watch-172-buicks-enclave/


  36. 36
    nuclearboy

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    Dec 4th, 2009 (10:53 am)

    stuart22: Whoop-di-do. These numbers mean little to the average consumer, whose interest in numbers is focused upon cost of operation (MPG)

    If you look back about a year or so in the archives you will see that each point (0.001 unit) of drag reduction added some distance (0.1 miles or something like that) to the cars electric range (I am too lazy to look it up right now). The lower drag also improves the highway mpg number.

    This does focus right in on what consumers care about.


  37. 37
    Blind Guy

     

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    Dec 4th, 2009 (10:59 am)

    The under side of these new cars is getting much smoother, so I am willing to give up some air drag for more ground clearance so our front bumper won’t drag leaveing our driveway.My wife is careful but our Prius has a 6 inch crack from dragging and I really don’t want that to happen again.


  38. 38
    nuclearboy

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    Dec 4th, 2009 (11:02 am)

    Van: And one more thing, when reading about how dimples might lower drag, some talked of basic drag and parasitic drag. The dimples were supposed to allow better air to flow into the void behind the car, thus reducing the “differential” pressure and improve efficiency at high speed. Any validity to that?

    Yes, there is validity to the dimpled surface reducing drag by tripping the boundary layer (stirring up the flow at the edge) and giving the flow the ability to flow along the ball a little further around the edge. The golf ball is the classic case. The dimples actually increase drag on the side of the ball but reduce the size of the wake (which is like a suction zone behind the ball) and the overall effect is a reduction in total drag.

    There is usually no universal truths in fluid flow and turbulence however. Vehicle aerodynamics are more complicated and I am not sure if dimples would help. The flow may already be turbulent.

    It would also be a pain to wax a dimpled car…..


  39. 39
    Bill

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    Dec 4th, 2009 (11:05 am)

    carcus1:
    I’m assuming he’s moving down or out, and not up.
    Commentor #5 on linked article said it better than I could:“Here’s some of his resume:CEO of Exide Technologies – BK
    VP – Chrysler – BK
    VP – GM – BK
    While @ Ford, in charge of development of Merkur Brand – NO SALES
    2008 salary @ GM – $6.9 Million.Feds got rid of the wrong guy. The only real winner that Lutz has been involved in was the initial development of the original Explorer. He is responsible for big ticket, low sales units – i.e. Viper, Prowler, Enclave, etc. He needs to be reassigned immediately – over rated and under performing. Just like the companies he’s worked for while he’s there. He may not be the reason for their failures but there seems to be some connection. He is the epitome of someone who moves when people see through his schtick and is what we like to call a corporate grimm reaper.”Lutz to be reassigned in GM shakeup, reports say
    http://www.autonews.com/article/20091204/OEM02/912049997/1180  

    Of course you would have done a much better job than Bob Lutz.

    It is always easy to be on the sidelines and criticize.


  40. 40
    nuclearboy

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    Dec 4th, 2009 (11:07 am)

    nuclearboy: If you look back about a year or so in the archives you will see that each point (0.001 unit) of drag reduction added some distance (0.1 miles or something like that) to the cars electric range (I am too lazy to look it up right now). The lower drag also improves the highway mpg number.

    http://www.hybridcars.com/news/chevy-volt-design-details-slowly-emerge-0814.html

    This article explains the economics of aerodynamics and how it will affect the window sticker mpg…


  41. 41
    carcus1

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    Dec 4th, 2009 (11:10 am)

    Bill: Of course you would have done a much better job than Bob Lutz.
    It is always easy to be on the sidelines and criticize.  

    I agree with you . . . on both counts.


  42. 42
    stuart22

     

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    Dec 4th, 2009 (11:15 am)

    nuclearboy:
    If you look back about a year or so in the archives you will see that each point (0.001 unit) of drag reduction added some distance (0.1 miles or something like that) to the cars electric range (I am too lazy to look it up right now).The lower drag also improves the highway mpg number.This does focus right in on what consumers care about.  

    I understand the importance of low drag numbers. My point is that this issue is a design concern – not a customer concern.


  43. 43
    Noel Park

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    Dec 4th, 2009 (11:21 am)

    ardvark: WSJ is reporting that Bob Lutz has been removed as gm’s director of marketing. Whitacre wants shift to younger people.

    #12

    God send that it shall be true!!


  44. 44
    Jon

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    Dec 4th, 2009 (11:27 am)

    What they dont like to tell you is that the drag force is proportional to the product of the drag coeficient *and* the frontal area. A low drag coefficient with higher frontal area means nothing.

    Not that GM isnt the only automaker to try to obscure this. They all do.


  45. 45
    Noel Park

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    Dec 4th, 2009 (11:31 am)

    nasaman: Hooray! My hope of buying an Ampera in Europe, touring the continent in it, then shipping this gorgeous, distinctively-styled sister to the Volt to a port in my home state of Florida may be back on track!

    #26

    Careful my friend. “Gray market” cars can be a total nightmare, that’s if you can get it into the country in the first place. If it’s not EPA/DOT certified, my understanding is that it will either go back or be crushed.


  46. 46
    CaptJackSparrow

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    Dec 4th, 2009 (11:31 am)

    I posted this yesterday on Dimples that improved the slipstream of a car…

    If aerodynamics plays a good part, why not “Dimple” the car. Myth Busters did it and the results shocked the hell out of them. Google it and watch the video. It’s halarious dumbfounded they were on the results.
    Sure it’s not attractive but slap the “Titliest” logo or “Ping”, “Wilson” or “MaxFlite”. Then have Tiger Woods drive it around. Or should he now be caller “Cheetah Woods”?
    Getit? Cheated on wife? Cheetah?

    AHAHAHAHAHAHAHAHAHAHAHAHAAAA!!!!!

    Serious though, the dimples worked.


  47. 47
    kdawg

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    Dec 4th, 2009 (11:32 am)

    carcus1: From April, 2008:“Enclave buyers belong to a highly coveted pool, sporting an average age of 53 and median annual household incomes of $130k. By appealing to high earners, the Enclave generates substantially higher revenues than its fellow Lambda triplets. J.D. Power reports recent average transaction prices of $38,479, $3500 greater than the mid-tier GMC Acadia and more than $5600 above the Saturn Outlook. Thanks to Enclave’s sales performance, Buick’s overall transaction prices increased 16.1 percent over the year, substantially outperforming the industry average of 0.6 percent.The actual sales figures, however, are less inspiring. At its current sales pace of about 45 – 50k units per year, Enclave deliveries lag behind such rivals as Lexus RX and Ford Edge, as well as its badge-engineered brother, the GMC Acadia. Those hoping for a Lambda-based home run will need to find another ballpark.”http://www.thetruthaboutcars.com/gm-death-watch-172-buicks-enclave/  (Quote)

    I’m glad you know how to use Google. The real truth is in 2007 the Enclave was kicking the butt of pretty much over every other GM car (not to mention the Prius), in 2008 gas spiked and sales were down (but this was the case for all cars), in 2009 the Enclave has had a 33% increase. For GM, this was/is one of their most popular cars (which was the original debate), and in my book a winner. I dont really care what Adrian Imonti wrote back in spring of 2008. He was also bashing the Lucerne and the Lacrosse which are also now doing great for GM. There were other bigger sales failures by Bob Lutz. You should have mentioned the Soltice/Sky instead of the Enclave (which I dont even know how much Bob was involved with).


  48. 48
    LauraM

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    Dec 4th, 2009 (11:37 am)

    carcus1: Commentor #5 on linked article said it better than I could:
    “Here’s some of his resume:
    CEO of Exide Technologies – BK
    VP – Chrysler – BK
    VP – GM – BK
    While @ Ford, in charge of development of Merkur Brand – NO SALES
    2008 salary @ GM – $6.9 Million.

    I don’t know enough about the other situations to comment, but you cannot seriously blame him for Chrysler’s bankruptcy. When he left, they were still profitable. Daimler ran them into the ground. That has nothing to do wtih Lutz.

    As far as GM–that was predetermined well before Lutz came on board. Whether his contributions were a positive or negative is beside the point. And up for debate. But he is definately not the cause of all of GM’s problems. What finally destroyed GM was the loan they had to take out to cover their pension and health care liabilities to the UAW retirees in 2003. Period. They’ve been living on borrowed time since then.


  49. 49
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    Dec 4th, 2009 (11:39 am)

    I took my Silverado crew cab and removed the mirrors. I then taped all the body seams, applied dimple tape to the whole thing and lowered it and installed a full length belly pan. It looks like crap but he CD number comes in at an amazing -.25. Yes that is MINUS .25. I have to set the parking brake now or it will roll backwards just sitting in my yard.


  50. 50
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    Dec 4th, 2009 (11:39 am)

    Loboc: A Corvette weighs just as much as any other car. More than some exotics.

    Actually, a Corvette, at about 3300#, is right there with the equivalent models from Porsche, Ferrari, et al. It’s just about 1/2 to 2/3 the price. And fiberglass is actually pretty strong stuff, and has good energy absorption capability in crashes. I’m living proof, having had a few racing “incidents” over the years. I hit a steel Mustang once, and it came off very second best.

    Is 3300# too heavy? Yes, IMHO, but “exotics” actually tend to weigh that much or more. I guess because they tend to load them up with luxury accessories and features. That’s why I’m so fond of the current Lotuses, although even they gain a couple of hundred pounds by the time they get here.


  51. 51
    Nuclearboy

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    Dec 4th, 2009 (11:42 am)

    stuart22: I understand the importance of low drag numbers. My point is that this issue is a design concern – not a customer concern.

    I agree. I don’t think people care other than car nerds (like you…. and me). Typically I don’t see GM advertising drag coefficients. It is the mpg number as you point out.

    Given our (unhealthy?) interest in everything Volt, Drag is a big deal at gm-volt.com.


  52. 52
    Noel Park

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    Dec 4th, 2009 (11:45 am)

    Bill: Of course you would have done a much better job than Bob Lutz.
    It is always easy to be on the sidelines and criticize.

    #39

    If I was making $6.9 million a year and couldn’t do any better than that I’d expect to get fired. Let alone going around the country carrying on like an arrogant know it all.


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    Dec 4th, 2009 (11:49 am)

    CaptJackSparrow: Sure it’s not attractive but slap the “Titliest” logo or “Ping”, “Wilson” or “MaxFlite”. Then have Tiger Woods drive it around.

    #46

    Somebody said yesterday the Tiger’s wife was getting an endorsement contract with Ping. So much for the All American Boy Buick spokesman. I wonder how this all plays with the Buick demographic?


  54. 54
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    Dec 4th, 2009 (11:51 am)

    Nuclearboy: I agree. I don’t think people care other than car nerds (like you…. and me).

    #51

    And me, LOL.


  55. 55
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    Dec 4th, 2009 (12:00 pm)

    Kyle: So its interesting that the 2e achieved a .15 cd but they did it with carbon fiber that is still not even close to being competitive with metal stamping techniques in terms of rate of production and ultimately cost. GM and the other majors don’t choose carbon fiber for large run vehicles because they are stuck in their ways its because these techniques are still not viable for large production runs. Aptera is a design study no more.

    This may be a really basic question–but how does carbon fiber affect cd?


  56. 56
    CaptJackSparrow

     

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    Dec 4th, 2009 (12:04 pm)

    OT but relevant to EV….

    5-6 months ago Li cells had cycle times of…
    80% DOD = 2000 cycles
    70& DOD = 3000 cycles

    Fast forward to today and now the specs read…
    80% DOD = 3000 cycles
    70% DOD = 5000 cycles
    http://www.thunder-sky.com/pdf/200964145219.pdf

    So with these new specs, in one year you can cycle 13.69 times in one day or if you cycled only once a day it would last 13.69 years.

    This is for LiFePO4, LiMn or Nano cathodes or Cobalt will vary but it’s still “Progress”.

    These have yet to hit the US soils because they are still new but available. Current suppliers here still have stock of the older models so depleting them is a priority.


  57. 57
    LauraM

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    Dec 4th, 2009 (12:10 pm)

    nasaman: Hooray! My hope of buying an Ampera in Europe, touring the continent in it, then shipping this gorgeous, distinctively-styled sister to the Volt to a port in my home state of Florida may be back on track!

    I would make sure before you do that that you have a mechanic available who can service the Ampera. Especially if GM hasn’t rolled out the Volt in Florida yet. The Volt incorporates a lot of new technology and lots of things can go wrong. And most mechanics won’t be familiar enough with the new tech to handle potential problems.


  58. 58
    Nuclearboy

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    Dec 4th, 2009 (12:26 pm)

    LauraM: but how does carbon fiber affect cd?

    Wind does not care if it flows over painted carbon, steal, or plastic. If the shape is the same, the flow is the same.

    Perhaps is is easier to shape the carbon fiber panels but this is really a manufacturing issue.


  59. 59
    CaptJackSparrow

     

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    Dec 4th, 2009 (12:26 pm)

    Post 57 should read….

    This is for LiFePO4 cells but LiMn or Nano cathodes or Cobalt
    will vary but it’s still “Progress”.

    Not

    This is for LiFePO4, LiMn or Nano cathodes or Cobalt
    will vary but it’s still “Progress”.


  60. 60
    Unni

     

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    Dec 4th, 2009 (12:30 pm)

    Prove us the point than just cd: How it translate to money.

    Put the shell of volt over a cruze – say us if this shell was on cruze you get this much mpg

    Put shell of ev1 over a cruze – say is the mpg

    Put a corvette shell over the cruze and say us the mpg.

    If possible put a Aptera Shell over cruze and say us the mpg.

    We will believe

    On Toyota windtunnel and GM windtunnel difference ( its old method and new method difference ) I think its like US gallon vs imperial gallon , GM tested in ford and Chrysler ones ( US ones ) they have to test in imperial ones also :-) . When you say the output its all mpg. Now we have to say Cd Old and Cd New.


  61. 61
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    Dec 4th, 2009 (12:31 pm)

    Herm: You are going to get great EV range out of the Volt, speed kills (your mileage).  (Quote)

    Wrong, stop and go traffic kills. The volt is heavy with it’s battery pack. Every time you have to get that weight moving again is whats going to kill the range.


  62. 62
    DonC

     

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    Dec 4th, 2009 (12:31 pm)

    Before getting into all the interesting developments in the executive suites, let me say that the Cd is very interesting. Basically this tells us, as has been suggested, that you don’t NEED to have a aerodynamic car look like a Prius. That’s one way but hardly the only way. FWIW the LEAF does not look like a Prius either. It’s also interesting to know that even published Cd numbers should be taken with a grain of salt.

    It’s great that GM has gone public with this. Kudos to Bob Bonniface.

    Finally, with respect to the claimed Cd for an Aptera, what we’re talking about is really an unverified hope. AFAIK that vehicle has never been in a wind tunnel. My personal guess is that an Aptera 2e, if it ever comes out of the garage, will have a Cd or .2, plus or minus .02.


  63. 63
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    Dec 4th, 2009 (12:32 pm)

    Nuclearboy: Wind does not care if it flows over painted carbon, steal, or plastic. If the shape is the same, the flow is the same.
    Perhaps is is easier to shape the carbon fiber panels but this is really a manufacturing issue.

    Oh. So the Aptera design could be made with steel, which would be cheaper, and it would still maintain its low cd? But range would suffer because steel is heavier?


  64. 64
    DonC

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    Dec 4th, 2009 (12:35 pm)

    LauraM: This may be a really basic question–but how does carbon fiber affect cd?

    As mentioned, not a thing per se. But it sure can cut the mass, which is a big part of the equation. It’s also happens that mass is the part of the equation that GM more or less blew off with the Volt.

    I’d love to see some big DOE grants for manufacturing with lighter materials. You don’t need composites though they have some advantages. Light weight steel would do just fine. The problem is that these are all well beyond the research stage so the grants would have to be for production.


  65. 65
    kgurnsey

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    Dec 4th, 2009 (12:38 pm)

    LauraM: This may be a really basic question–but how does carbon fiber affect cd?  (Quote)

    It doesn’t, but it affects the production rate. The point, I believe, was that the Aptera has a great Cd, but couldn’t be produced in mass quantities due to the materials chosen (not to mention the rest of the design, practicality, features, etc…). Hence it’s a very nice design study, but not many will end up in driveways (if any at all). I’m assuming that makes the Volt better than the Aptera in Kyle’s eyes, even with a higher Cd.


  66. 66
    CorvetteGuy

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    Dec 4th, 2009 (12:39 pm)

    That’s cool. Wikipedia claims a bullet CD is 0.295 at sub-sonic speeds.


  67. 67
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    Dec 4th, 2009 (12:42 pm)

    I know that the NY Times is a terrible paper and you can never believe anything in it, but it is reporting that Whitacre has moved Mark Reuss into a top position as head of global design. Lutz stays on with expanded responsibilities. I’ll note that Reuss is in his mid-40s or something and comes from engineering. Sales and Marketing are combined and report to Reuss.

    The notion is that Whitacre wants more emphasis on product, which seems to me to be an obvious but good thing. (Not saying anyone previously in these positions was bad at this BTW).

    We’ll see how this unfolds.

    http://wheels.blogs.nytimes.com/2009/12/04/car-guy-now-in-charge-after-gms-latest-shake-up/


  68. 68
    kgurnsey

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    Dec 4th, 2009 (12:44 pm)

    Fred: Wrong, stop and go traffic kills. The volt is heavy with it’s battery pack. Every time you have to get that weight moving again is whats going to kill the range.  (Quote)

    Wrong again. Well, more accurately, you’re both right. While stop and go does kill, so does speed due to the added aerodynamic load. For EVs though, for the most part the slower you travel, assuming you don’t have to stop and start, the longer your range will be.


  69. 69
    DonC

     

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    Dec 4th, 2009 (12:50 pm)

    kgurnsey: It doesn’t, but it affects the production rate.

    It doesn’t have to affect production rates. Keep in mind that they make boats out of this stuff 24/7. (The designer of the Aptera came from boat building).

    Aptera just doesn’t have the money at the moment. It may get it or not. It takes at least $200M, and more realistically $350M, and Aptera raised about 1/10th of that.

    It would be unfortunate if people concluded that the problem was the material for the shell. In fact the shell was one of the few parts which could have been used to start production — Aptera could have produced the shells in small runs without a huge cost penalty. It’s all the other parts, including battery pack, motor, and control electronics, where you need volume to drive down costs.


  70. 70
    DonC

     

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    Dec 4th, 2009 (12:54 pm)

    Looks like Lutz does not really have an expanded role — more like he’s been shifted to an advisory role. Big thing is that it looks like Whitacre may be the CEO until the IPO, which may be a couple of years out:

    http://news.yahoo.com/s/nm/20091204/bs_nm/us_gm_leadership


  71. 71
    LauraM

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    Dec 4th, 2009 (1:09 pm)

    DonC: As mentioned, not a thing per se. But it sure can cut the mass, which is a big part of the equation. It’s also happens that mass is the part of the equation that GM more or less blew off with the Volt.
    I’d love to see some big DOE grants for manufacturing with lighter materials. You don’t need composites though they have some advantages. Light weight steel would do just fine. The problem is that these are all well beyond the research stage so the grants would have to be for production.

    From what I understand, making the Volt out of Carbon fiber (or maybe even lightweight steel) would add at least $10,000 to the final price? That might be an option for the Converj, but not the Volt, when they’re trying to reduce costs as much as possible.

    I would also love to see some DOE grants, or any kind of grants, for production with lightweight materials. That’s one of our major problems in this country, IMHO. We fund research, but after that, we leave it to other countries to fund the production part. Which is one of the reasons we’re losing our manufacturing base.


  72. 72
    kgurnsey

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    Dec 4th, 2009 (1:09 pm)

    DonC: It doesn’t have to affect production rates. Keep in mind that they make boats out of this stuff 24/7. (The designer of the Aptera came from boat building). Aptera just doesn’t have the money at the moment. It may get it or not. It takes at least $200M, and more realistically $350M, and Aptera raised about 1/10th of that. It would be unfortunate if people concluded that the problem was the material for the shell. In fact the shell was one of the few parts which could have been used to start production — Aptera could have produced the shells in small runs without a huge cost penalty. It’s all the other parts, including battery pack, motor, and control electronics, where you need volume to drive down costs.  (Quote)

    I agree completely, however the point that I believe was being raised by Kyle is that the Aptera could not achieve the Volt’s level of production due to the material chosen for the body shell. It’s faster to stamp and weld steel on a production line that to form and cure carbon fiber in batches.

    I’m sure that someone could come up with a manufacturing process to produce high colume carbon fiber bodyshells, if it hasn’t happened already, I was just trying to answer LauraM with my interpretation of Kyle’s post.


  73. 73
    ceric

     

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    Dec 4th, 2009 (1:19 pm)

    Wiki site
    http://en.wikipedia.org/wiki/Drag_coefficient
    (right column)
    shows that the length significantly affect the Cd.
    Compare the Cd of a cube, long cylinder, and short cylinder.
    It is very very difficult to have low Cd for a short hatch back like Nissan Leaf or Honda Fit. That is also why long sedan like Lexus LS could have low Cd, but a short Beetle does not even though it “looks” like it has low drag.

    Dimples is a great example that aerodynamics is easy to understand but very difficult to optimize further after you reach a certain stage. I read it somewhere that a reduction of 0.02 in Cd improves 1mpg on highway. Don’t whether it is still true.

    Anyway, Cd is a function of air velocity and density. Data from different tests are not so comparable. Like any road test of vehicles (such as 0-60 time), you have to test it on the same facility to compare them objectively.


  74. 74
    Streetlight

     

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    Dec 4th, 2009 (1:25 pm)

    This is not about Bob Lutz only. A fairly sizable shake-up. http://www.detnews.com/article/20091204/AUTO01/912040407/GM-giving-Lutz-new-role
    Lutz is the highest level exec under Whitacre. There’s no change to his title. Only his assignment. I believe Lutz likely suggested many if not all these jobs realigned. Mark Reuss son of a former GM pres named GM North America.
    VP Susan Docherty is bumped-up big time making her sales service and marketing ops. And the top labor relations Diana D. Tremblay adds manufacturing – most interesting. This bodes well for GM’s unions.
    Lutz started to retire more than once. He stayed to help guide GM through its cash-depletion maze. That’s not to say anyone knows what Whitacre really thinks.


  75. 75
    Dr. Ibringdoh

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    Dec 4th, 2009 (1:32 pm)

    Loboc: A Corvette weighs just as much as any other car. More than some exotics.Fiberglass itself is not necessarily lighter than steel. You need more frame to support it as fiberglass is a poor structural material. If you look at a wrecked ‘Vette or boat, the story will be clear. Fiberglass shatters and cracks on impact. If you put holes in it (like for windows and door handles and things), it weakens the structure.Now if you use reinforced/modified fiberglass (such as carbon fiber), you can achieve good weight vs structure. But, it is VERY expensive.  (Quote)

    Fiberglass is not a poor structural material. If formulated and compounded properly, it can be stronger, less prone to fatigue, and more durable than painted steel. It can be used to make bridge beams.

    http://www.compositesworld.com/articles/smc-flexes-muscles-in-ampx93otherampx94-markets.aspx

    https://www.ksu.edu/media/webzine/0102/bridge.html

    Respectfully,

    Dr. Ibringdoh


  76. 76
    JohnK

     

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    Dec 4th, 2009 (1:38 pm)

    CaptJackSparrow: Serious though, the dimples worked.

    Yes, dimples work. There is an equivalent used in airplane design, though it is mostly used as a “fix” when there is a problem. The thing I am talking about are small, usually plastic ridges that are glued to the wing or surface where airflow is a problem. These break up “laminar flow” into a controlled but beneficial turbulence. Laminar flow is overall a good thing, but it can only be maintained over a portion of the front side (windward?) of an object. Once laminar flow is broken, it is better to have “attached turbulence”. That is what dimples do.


  77. 77
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    Dec 4th, 2009 (1:52 pm)

    kgurnsey: I agree completely, however the point that I believe was being raised by Kyle is that the Aptera could not achieve the Volt’s level of production due to the material chosen for the body shell. It’s faster to stamp and weld steel on a production line that to form and cure carbon fiber in batches.
    I’m sure that someone could come up with a manufacturing process to produce high colume carbon fiber bodyshells, if it hasn’t happened already, I was just trying to answer LauraM with my interpretation of Kyle’s post.

    I appreciate the information. Thank you for the information. I knew that carbon fiber was expensive, but I had no idea production was even an issue.

    If production is the main issue, it sounds to me like a great opportunity for luxury cars. It explains why Tesla choose to use it…


  78. 78
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    Dec 4th, 2009 (2:07 pm)

    For simulated Volt performance differences using the more realistic 0.28 aero drag coefficient, check out comments at http://gm-volt.com/forum/showthread.php?p=33496#post33496

    Tom


  79. 79
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    Dec 4th, 2009 (2:09 pm)

    DonC: Looks like Lutz does not really have an expanded role — more like he’s been shifted to an advisory role. Big thing is that it looks like Whitacre may be the CEO until the IPO, which may be a couple of years out:

    Given how much reshuffling he’s doing, it definately looks like he plans to stay. I’d hate to think they’re going to go through this amount of reshuffling and redirection twice. Whiteacre definately wouldn’t be my first choice (I would prefer someone with more manufacturing experience), but it’s not like they have too many options at this point. So, at this point, I think they should just stick with him rather than continue their search.


  80. 80
    kgurnsey

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    Dec 4th, 2009 (2:10 pm)

    LauraM: I appreciate the information. Thank you for the information. I knew that carbon fiber was expensive, but I had no idea production was even an issue. If production is the main issue, it sounds to me like a great opportunity for luxury cars. It explains why Tesla choose to use it…  (Quote)

    It has been used extensively in the high end supercar market for the past decade. The first produciton car to use a carbon fiber monocoque was the McLaren F1 in 1992.

    http://en.wikipedia.org/wiki/Mclaren_f1

    The production for carbon fiber is different from more conventional materials, and differs in some signifigant ways from fiberglass as well. However, it is becoming more mainstream. Prices are coming down, and production is ramping up.

    http://news.cnet.com/Here-comes-the-everyday-carbon-fiber-car/2100-1008_3-6114289.html


  81. 81
    Loboc

     

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    Dec 4th, 2009 (2:16 pm)

    Dr. Ibringdoh:
    Fiberglass is not a poor structural material.If formulated and compounded properly, it can be stronger, less prone to fatigue, and more durable than painted steel.It can be used to make bridge beams.http://www.compositesworld.com/articles/smc-flexes-muscles-in-ampx93otherampx94-markets.aspxhttps://www.ksu.edu/media/webzine/0102/bridge.htmlRespectfully,Dr. Ibringdoh  

    As it is currently done (ie. hand lay-up or chopper gun), fiberglass is not very good for structure. You need steel or wood or another ‘stiffener’ in the lay-up to make it strong. Which also makes it heavier.

    Yeah, as i mentioned, advanced molding processes and materials not currently used for boats or cars (and more expensive like carbon-fiber) could make this better. It’s just not economically feasible right now. How many cars do you see made of fiberglass? Mostly it’s plastics like PVC.

    And I never said fiberglass was a poor impact material. It just breaks apart instead of bending to absorb the energy. My point was that after impact, you have a real mess with fiberglass.


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    Starcast

     

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    Dec 4th, 2009 (2:17 pm)

    Dave G: As a point of reference, the Aptera 2e comes in with a coefficient of drag at .15http://www.aptera.com/love.php  (Quote)

    Aptera is a motorcycle not a car. 3 wheels = Motorcycle.


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    CorvetteGuy

     

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    Dec 4th, 2009 (2:23 pm)

    Nuclearboy: I agree. I don’t think people care other than car nerds (like you…. and me). Typically I don’t see GM advertising drag coefficients. It is the mpg number as you point out.
    Given our (unhealthy?) interest in everything Volt, Drag is a big deal at gm-volt.com.

    Remember when Carter was President and we had those ‘oil embargos’ ? I believe that was when “auto aerodynamcs” started to be a big concern; as far as fuel mileage goes. I recall that is about the time Chrysler started making their cars with the low, pointy noses and low rooflines. Ya’know… they were kinda tapered at both ends like a POS….

    Now that’s an old car nerd for you if you can remember those days!


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    Dec 4th, 2009 (2:32 pm)

    Starcast: Aptera is a motorcycle not a car. 3 wheels = Motorcycle.  (Quote)

    Technically yes, but this is one of those grey areas. It’s essentially a 3 wheeled car. Transport Canada makes a distinction between open and closed passenger compartments, classifying one as motorcycle and the other essentially as a car, requiring automotive safety requirements to be followed. In a broad sense, it’s a destinction between trikes, which are obviously motorcycles, and things like the Aptera. If it looks like a car, and will be used by the public as a car would be used, which the Aptera does and will be, then there is a good argument to be made that the consumer will assume that said vehicle will be as safe as a car in a collision, which a motorcycle is not.

    Call it whatever you want, but the public will not be buying it to use as a motorcycle. It’s a car.


  85. 85
    kgurnsey

     

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    Dec 4th, 2009 (2:38 pm)

    In case it wasn’t clear in my post above, I am aware that in most, if not all States, three wheeled vehicles are classed as motorcycles. My example was a contrast with how Transport Canada views the same issue.

    It’s well known that several small auto manufacturers are using this loophole to design three wheeled cars for the US market in order to get around expensive safety requirements.

    If it looks like a car, smells like a car, tastes like a car…


  86. 86
    Rashiid Amul

     

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    Dec 4th, 2009 (2:45 pm)

    CorvetteGuy:
    Remember when Carter was President and we had those ‘oil embargos’ ?

    Ah, I remember those days. How wonderful they were.
    My father was driving a 1966 Rambler Ambassador.
    He would get angry very often when he would be in line for an hour, and the out-of-gas sign would appear on the car directly in front of him. I was too young to drive back then, thank goodness.

    I can only imagine the uproar today if this was to happen again.


  87. 87
    Starcast

     

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    Dec 4th, 2009 (2:55 pm)

    kgurnsey: In case it wasn’t clear in my post above, I am aware that in most, if not all States, three wheeled vehicles are classed as motorcycles. My example was a contrast with how Transport Canada views the same issue.It’s well known that several small auto manufacturers are using this loophole to design three wheeled cars for the US market in order to get around expensive safety requirements.If it looks like a car, smells like a car, tastes like a car…  (Quote)

    Can the Aptera meet all the “Car” Requirements? If not it’s not a car.


  88. 88
    Gary

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    Dec 4th, 2009 (3:01 pm)

    Data I read the Prius came in at .25 and a lot less expensive.


  89. 89
    Noel Park

     

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    Dec 4th, 2009 (3:08 pm)

    Starcast: Can the Aptera meet all the “Car” Requirements? If not it’s not a car.

    #89

    I believe that Congress recently passed legislation to allow 3 wheeled vehicles, and particularly the Aptera, to be classified as cars for the purpose of accessing the gov’t loans to assist hybrid/BEV development. The legislation was introduced by the U.S. Rep. from the greater San diego area where Aptera is located, if memory serves.

    The requirements are very similar to the Canadian ones described by kgurnsey above.

    With the “management” currently in place at Aptera, it is highly problematic that they will survive to actually produce any cars for sale, IMHO. I mean Saleen? Come on guys!

    Some cynics believe that the folks currently running the show came on specifically so that they could get their hands on the gov’t loan jackpot.


  90. 90
    Rashiid Amul

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    Dec 4th, 2009 (3:11 pm)

    Gary: Data I read the Prius came in at .25 and a lot less expensive.  

    Thus the comment from the article above:
    “I’d like to test the Volt in the same tunnel where Toyota got their 0.25 value,” he teased.


  91. 91
    BillR

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    Dec 4th, 2009 (3:18 pm)

    Well, I thought the Volt was supposed to be GM’s most aerodynamic vehicle that the currently produce. However, looks like the Opel Insignia has it beat!!

    http://green.autoblog.com/2008/10/02/paris-2008-debut-of-the-opel-insignia-ecoflex/


  92. 92
    kgurnsey

     

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    Dec 4th, 2009 (3:22 pm)

    Starcast: Can the Aptera meet all the “Car” Requirements? If not it’s not a car.  (Quote)

    In Canada, it’s essentially classed as a car, in that it is required to pass safety regulations. Whether or not it meets the requirements to be allowed on Canadian roads is beside the point.

    The classification dictates the requirements that must be met, not the other way around. Not meeting the requirements does not change the classification, it just means the vehicle failed to meet the necessary requirements for that class.

    The point is that if Aptera are not willing to toss one into a wall to prove the safety of thier vehicle, it’s won’t be allowed. If it were classed as a motorcycle, like it is in the States, then that proof wouldn’t be necessary.


  93. 93
    pKIO3

     

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    Dec 4th, 2009 (3:23 pm)

    OT – Interesting review of Volt in Canada.

    http://www.nationalpost.com/cars/story.html?id=2301860&p=1


  94. 94
    Todd

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    Dec 4th, 2009 (3:23 pm)

    Dave G: As a point of reference, the Aptera 2e comes in with a coefficient of drag at .15http://www.aptera.com/love.php  (Quote)

    I think the drivers seat alone of the Volt has more room than the entire Aptera.


  95. 95
    FLASH

     

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    Dec 4th, 2009 (3:25 pm)

    Rashiid Amul: Ah, I remember those days. How wonderful they were.My father was driving a 1966 Rambler Ambassador.He would get angry very often when he would be in line for an hour, and the out-of-gas sign would appear on the car directly in front of him. I was too young to drive back then, thank goodness.I can only imagine the uproar today if this was to happen again.  (Quote)

    I am too young as well, thankfully–The only thing I can liken it to is when I rescued my sister and some friends from hurricane Katrina. Fuel shortage was CRAZY–I mean HOURS in ALL directions….:)


  96. 96
    Todd

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    Dec 4th, 2009 (3:27 pm)

    Gary: Data I read the Prius came in at .25 and a lot less expensive.  (Quote)

    I think you need to check this out. I went to the Toyota site and put in all the features that come on the Volt. The total for the Hybrid Prius – $34,798.00.


  97. 97
    kgurnsey

     

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    Dec 4th, 2009 (3:28 pm)

    Noel Park: #89I believe that Congress recently passed legislation to allow 3 wheeled vehicles, and particularly the Aptera, to be classified as cars for the purpose of accessing the gov’t loans to assist hybrid/BEV development. The legislation was introduced by the U.S. Rep. from the greater San diego area where Aptera is located, if memory serves.The requirements are very similar to the Canadian ones described by kgurnsey above.With the “management” currently in place at Aptera, it is highly problematic that they will survive to actually produce any cars for sale, IMHO. I mean Saleen? Come on guys!Some cynics believe that the folks currently running the show came on specifically so that they could get their hands on the gov’t loan jackpot.  (Quote)

    I read somewhere about that, but I’m not sure that the requirements are the same. Transport Canada requires closed cockpit 3 wheeled motorcycles to pass the same safety tests that cars have to pass. I’m not sure whether this requirement extends to the legislation passed in the States. It’s a very expensive process to go through, and most manufacturers who are building three wheeled cars are doing so to avoid that process, which they wouldn’t be able to afford.

    I would be surprised if the legislation included a requirement like this, since it would undermine the reason for producing the Aptera (as others like it) as motorcycles in the first place.


  98. 98
    Starcast

     

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    Dec 4th, 2009 (3:33 pm)

    Noel Park: #89I believe that Congress recently passed legislation to allow 3 wheeled vehicles, and particularly the Aptera, to be classified as cars for the purpose of accessing the gov’t loans to assist hybrid/BEV development. The legislation was introduced by the U.S. Rep. from the greater San diego area where Aptera is located, if memory serves.The requirements are very similar to the Canadian ones described by kgurnsey above.With the “management” currently in place at Aptera, it is highly problematic that they will survive to actually produce any cars for sale, IMHO. I mean Saleen? Come on guys!Some cynics believe that the folks currently running the show came on specifically so that they could get their hands on the gov’t loan jackpot.  (Quote)

    LOL “Some cynics believe that the folks currently running the show came on specifically so that they could get their hands on the gov’t loan jackpot.”

    Me thinks there is a lot of that going on.


  99. 99
    Mike-o-Matic

     

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    Dec 4th, 2009 (3:44 pm)

    Fred:
    Wrong, stop and go traffic kills.The volt is heavy with it’s battery pack.Every time you have to get that weight moving again is whats going to kill the range.  

    Yes, it takes more energy to get it going. But you’re forgetting that greater mass at speed means higher kinetic energy, much of which will be recaptured by the regen braking when the car slows down.


  100. 100
    Todd

     

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    Dec 4th, 2009 (3:46 pm)

    kgurnsey: Wrong again. Well, more accurately, you’re both right. While stop and go does kill, so does speed due to the added aerodynamic load. For EVs though, for the most part the slower you travel, assuming you don’t have to stop and start, the longer your range will be.  (Quote)

    So those of us who are really good at hyperdriving should do very well with the Volt as we time the lights and roll on and on at 35~45mph through the city streets. I have about twenty lights on my commute but rarely have to stop at more than three.


  101. 101
    dagwood55

     

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    Dec 4th, 2009 (3:59 pm)

    Todd: Prius

    Where did you get the Volt price and options sheet?


  102. 102
    Noel Park

     

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    Dec 4th, 2009 (4:02 pm)

    Starcast: Me thinks there is a lot of that going on.

    #100

    Yeah. Me too.

    Not to mantion any names, but allcarselectric.com has a report today that the release of the Fisker Karma is going to be delayed from this month until September 2010. I’m not holding my breath.


  103. 103
    kgurnsey

     

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    Dec 4th, 2009 (4:03 pm)

    Mike-o-Matic: Yes, it takes more energy to get it going. But you’re forgetting that greater mass at speed means higher kinetic energy, much of which will be recaptured by the regen braking when the car slows down.  (Quote)

    “Much of which” would be a bit of an overstatement. The Mini E is achieving about 20%, and that’s on the extreme end for EVs as the regen is very heavy, as Lyle could attest (and has). There are several reasons why it’s difficult to achieve high regen, especially at low speeds. Electric railcars achieve about 30% or so, and that’s about as high as it gets. Hydraulic regen can get you up into the mid 40′s.


  104. 104
    kgurnsey

     

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    Dec 4th, 2009 (4:10 pm)

    Todd: So those of us who are really good at hyperdriving should do very well with the Volt as we time the lights and roll on and on at 35~45mph through the city streets. I have about twenty lights on my commute but rarely have to stop at more than three.  (Quote)

    I would expect so, as long as you don’t have the shit lever in “L”. ;)


  105. 105
    kgurnsey

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    Dec 4th, 2009 (4:12 pm)

    Umm. That should have been “shiFt” How embarassing…

    Insert Freud reference here…


  106. 106
    Rashiid Amul

     

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    Dec 4th, 2009 (4:17 pm)

    FLASH:
    I am too young as well, thankfully–The only thing I can liken it to is when I rescued my sister and some friends from hurricane Katrina.Fuel shortage was CRAZY–I mean HOURS in ALL directions….:)  

    That was a very sad time, Flash. It was heart breaking watching it on TV. I can’t imagine what it would have been like to actually live through it. I hope you and your family came out of that okay.


  107. 107
    Nelson

     

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    Dec 4th, 2009 (4:28 pm)

    Dr. Ibringdoh: Nelson

    A car doesn’t only move through air, it drags itself on pavement. I’m thinking a cars COD should take into account the COF (coefficient of friction) as well.

    NPNS!


  108. 108
    Loboc

     

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    Dec 4th, 2009 (4:34 pm)

    CorvetteGuy:
    Remember when Carter was President and we had those ‘oil embargos’ ? I believe that was when “auto aerodynamcs” started to be a big concern; as far as fuel mileage goes. I recall that is about the time Chrysler started making their cars with the low, pointy noses and low rooflines. Ya’know… they were kinda tapered at both ends like a POS….Now that’s an old car nerd for you if you can remember those days!  

    I coulda swore it was Nixon that presided over that mess. First oil embargo was like 1973.


  109. 109
    Rashiid Amul

     

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    Dec 4th, 2009 (4:35 pm)

    kgurnsey: Umm.That should have been “shiFt”How embarassing…Insert Freud reference here…  

    Dang that was funny. I didn’t even notice it until you mentioned it.
    I had a good laugh with that one. Thanks.

    +1


  110. 110
    CaptJackSparrow

     

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    Dec 4th, 2009 (4:45 pm)

    Brake regen is not as easy/simple as it sounds.
    Let’s take a simple example of an induction mototr used as a generator. The ICE turns the coils and another set of coils uses external energy from a battery source to generate a magnetic field for the stator coils to cross the flux lines. The ICE turns at a steadt RPM. Simple concept.

    In brake regen replace the ICE with kenetic energy from the car. Now the RPM is very dynamic and the RPM decelerates. In the begining of brake regen, voltage/power is applied from the batt pack to the coils so a magnetic field is present and therefore generates power to deliver to the batt pack. Lenz Law is the braking effect you feel. BUT as the generator rpm decelerates so does power production and at some point, Voltage will be less than the batt pack and the regen power is useless because in order for current to flow into the batt pack you MUST have a higher voltage applied. Sure you can apply more power into the coils but that will pull from the batt pack. As you increase power to the coils, there is an intersect point where kenetic energy rpm is insufficient for power production and it’s a negative hit on the batt pack.
    I theorize that somewhere between 25-15mph brake regen is useless and if it is used for anything, it is used to be shunted to ground to keep the Lenz laww effect of braking then the mechanical brakes kick in.


  111. 111
    Monroe

     

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    Dec 4th, 2009 (5:35 pm)

    Dave G: As a point of reference, the Aptera 2e comes in with a coefficient of drag at .15
    http://www.aptera.com/love.php  

    Too bad Aptera is gonna fail.


  112. 112
    DaveP

     

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    Dec 4th, 2009 (6:02 pm)

    Blind Guy: The under side of these new cars is getting much smoother, so I am willing to give upsome air drag for more ground clearance so our front bumper won’t drag leaveing our driveway.My wife is careful but our Prius has a 6 inch crack from dragging and I really don’t want that to happen again.  

    Ah, yes. The “Concrete Drag Coefficient”. :) I have that problem with my ’96 Eclipse GSX. Which otherwise had a .29 Cd for air. And probably one of the lowest total drag numbers around since it’s so short I hit my head on the roof going over bumps. Ooof. ;)

    Also, somebody above mentioned that aerodynamic drag was related to velocity squared, which is true, but I think it’s actually more important to note that therefore power required is related to velocity cubed. (Because the power required to force an object through air is the drag * velocity).

    Which is why it is so vitally important for a car to have low drag to preserve high mileage for those of us that drive with high velocity. :) For those of you driving slowly, it doesn’t matter nearly as much. But that is no excuse to add a foam ball to the top of your antenna, or anything. ;)

    As usual, wikipedia has a nice explanation (1/3 of the way down the page) http://en.wikipedia.org/wiki/Drag_(physics)


  113. 113
    pinetree

     

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    Dec 4th, 2009 (6:04 pm)

    “The base Prius with the smaller wheels may come in lower, but we don’t offer 15 inch wheels.”

    I think that says it all. “Most Toyota Priuses sold probably beat our car, but we’re going to cheat by simply claiming we don’t compete with that version.” You have a great thing here, GM– don’t tarnish it by cheating in your marketing materials like this. It makes you sound like car salesmen.


  114. 114
    Pat

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    Dec 4th, 2009 (6:11 pm)

    Lou should start paying attention to the production on time & in volume ..to beat the expected arrival of Leaf & other EV around the same time …typ of GM talk a lot than deliver a lot …main reason they went bankrupt …Look at Japanese, Koreans they deliver than talk ..just the opposite of GM, Ford etc


  115. 115
    Dave G

     

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    Dec 4th, 2009 (6:18 pm)

    drag queen coefficient?


  116. 116
    CorvetteGuy

     

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    Dec 4th, 2009 (6:37 pm)

    Loboc: I coulda swore it was Nixon that presided over that mess. First oil embargo was like 1973.  

    I’m no historian. Coulda been Nixon. I do remember ‘aerodynamics’ being the excuse/reason for some funny shaped vehicles. Olds and Chevy had a bullet-shaped minivan, but the name escapes me right now. Just gettin’ old.

    I hope the VOLT gets here before I forget why I wanted it!


  117. 117
    LRGVProVolt

     

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    Dec 4th, 2009 (6:45 pm)

    #45

    Noel Park:
    #26Careful my friend.“Gray market” cars can be a total nightmare, that’s if you can get it into the country in the first place.If it’s not EPA/DOT certified, my understanding is that it will either go back or be crushed.  

    Nasaman, you do have to check to see if the Ampera meets those EPA/Dot requirements. Noel Park is correct. You would be required to spend a lot of money to bring it into compliance if at all possible. The safe choice is to get a Volt.

    Happy trails to you ’til we meet again.


  118. 118
    DaveP

     

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    Dec 4th, 2009 (6:53 pm)

    LRGVProVolt:
    Nasaman, you do have to check to see if the Ampera meets those EPA/Dot requirements. Noel Park is correct. You would be required to spend a lot of money to bring it into compliance if at all possible. The safe choice is to get a Volt.Happy trails to you ’til we meet again.  

    Of course if the trim panels are more or less compatible you might be able to acquire and then fit an Ampera grill on the Volt or something. :)


  119. 119
    Dan Petit

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    Dec 4th, 2009 (7:06 pm)

    Bob mentioned that the Prius CD was actually .30 in all it’s competitor’s wind tunnels. Well, you can’t deny that .30 to be erroneous by twenty percent if they are claiming it to be .25.

    TWENTY PERCENT!!! Scientifically, there is not any excuse whatsoever for any equipment to be that inaccurate!! The greatest tolerance for confidence level is FIVE percent. Not TWENTY percent!!

    Did you know that if twenty percent of the sulphur atoms in the sulphuric acid (half water/half acid) get stuck onto the lead plates in your auto, that, may PCM’s become unable to process properly in conjuction with the slight voltage surges from worn down alternator brushes? (Although they still have plenty of reserve to “start the engine”, yet not run software).
    (The very best 12 volt battery is the original part number of the original brand!!!)
    (TRUST ME ON THIS ONE THING!)
    (Two more computers blown up this week and one more non-GM automatic truck transmission blown up (with the $1200 LCD Instrument Panel Cluster at the same time!!) this week from that awful battery brand everyone here knows I dislike not just a little bit).

    Toyota processors apparently can function far below that 20 percent, but, to me, this certainly proves that Toyota certainly knows that a 20 percent confidence level is the worst (sleaziest) tolerance level to externally represent anything. (Esp. to the public).

    Not at all impressive.


  120. 120
    Nuclearboy

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    Dec 4th, 2009 (7:21 pm)

    CorvetteGuy: I’m no historian. Coulda been Nixon. I do remember ‘aerodynamics’ being the excuse/reason for some funny shaped vehicles. Olds and Chevy had a bullet-shaped minivan, but the name escapes me right now. Just gettin’ old.

    I’m no historian either but do have my version of events in memory.

    Nixon/Ford were in during the actual fuel crisis. Carter took office and setoff a bunch of energy initiatives which for which he should be given credit (He also wanted to legalize pot and thought the Iranian Ayatolla’s were men of the cloth that he could work with, much better than that Western leaning Shah).

    Somewhere in the mid 70′s, the speed limit dropped to 55 nationwide (felt like crawling on the highway) and there were many solar projects and I remember seeing fleets of tiny electric cars (They looked like a modern hugo).


  121. 121
    DonC

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    Dec 4th, 2009 (7:22 pm)

    LauraM: f production is the main issue, it sounds to me like a great opportunity for luxury cars. It explains why Tesla choose to use it…

    Production isn’t really an issue. A company like FiberForge, which uses a high-tech fiber placement head to lay thermoplastic tape at high speeds into “tailored blanks that can be heated and compressed in a mold, could make parts in just about any number as quickly as you could stamp steel.

    It’s really a chicken and egg problem. Since there isn’t a lot of demand, no one has is willing to invest in the production equipment needed to make parts in great volume. Because no one has the production equipment, costs per piece are high. And no manufacturer wants to order the higher priced parts — hence no demand.

    At some point you’d hope that the higher CAFE standards will change this by igniting a heretofore absent virtuous spiral.

    BTW Aptera shell is made from a composite not carbon fiber. It could have been made from any number of other materials, including lightweight steel or aluminum. There a plenty of alternatives that would dramatically reduce vehicular mass.


  122. 122
    Nuclearboy

     

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    Dec 4th, 2009 (7:25 pm)

    Nuclearboy: I remember seeing fleets of tiny electric cars (They looked like a modern hugo).

    Some fun facts. History is repeating itself. Will electrics die out again?

    1974
    Vanguard-Sebring’s CitiCar makes its debut at the Electric Vehicle Symposium in Washington, D.C. The CitiCar has a top speed of over 30 mph and a reliable warm-weather range of 40 miles. By 1975 the company is the sixth largest automaker in the U.S. but is dissolved only a few years later.

    (The CroMagnon Volt)

    1975
    The U.S. Postal Service purchases 350 electric delivery jeeps from AM General, a division of AMC, to be used in a test program.

    1976
    Congress passes the Electric and Hybrid Vehicle Research, Development, and Demonstration Act. The law is intended to spur the development of new technologies including improved batteries, motors, and other hybrid-electric components.

    (Sounds Familiar)

    1988
    Roger Smith, CEO of G.M. , agrees to fund research efforts to build a practical consumer electric car. G.M. teams up with California’s AeroVironment to design what would become the EV1, which one employee called “the world’s most efficient production vehicle.” Some electric vehicle enthusiasts have speculated that the EV1 was never undertaken as a serious commercial venture by the large automaker.


  123. 123
    Dave K.

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    Dec 4th, 2009 (7:41 pm)

    Just back from the L.A. Auto Show. The Volt and the Converj are being displayed. The Cruze is there in Viridian Joule and a bright bronze color. Fisker is showing off 2 models. The Sunset being a convertible with a very nice brown interior.

    The Converj looks awesome in person. With a solid “high end” look.

    Converj%20LA09.jpg

    The Cruze looks very good as well. GM is not allowing open door sit-in as the representative said, “It’s pre production”.

    Cruze%20LA09.jpg

    Ford and Chrysler are not showing their electric cars. I had a short chat with a Chrysler representative. The word is there will be four colors. Two of these being silver and yellow.

    Below is a link to a short movie clip showing the Volt display. You will see the Volt singers as they complete their presentation. I asked one of them what the name of the song was that they just sang. The reply was, “The Chevy Volt Song”. I did not capture sound during the presentation. But, I can tell you it sounds like a cross between a traditional Irish jig and a nursery rhyme.

    http://garfwod.250free.com/Photos/Volt%20LA%2009%20movie.MOV

    The Buick display looks very classy. The new line does not look like something one would see at senior day in the golf course parking lot.

    =D~


  124. 124
    DonC

     

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    Dec 4th, 2009 (7:46 pm)

    Nicely done.

    Tom: For simulated Volt performance differences using the more realistic 0.28 aero drag coefficient, check out comments at http://gm-volt.com/forum/showthread.php?p=33496#post33496


  125. 125
    Bob G

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    Dec 4th, 2009 (7:47 pm)

    CaptJackSparrow: Brake regen is not as easy/simple as it sounds.
    Let’s take a simple example of an induction mototr used as a generator. The ICE turns the coils and another set of coils uses external energy from a battery source to generate a magnetic field for the stator coils to cross the flux lines. The ICE turns at a steadt RPM. Simple concept.In brake regen replace the ICE with kenetic energy from the car. Now the RPM is very dynamic and the RPM decelerates. In the begining of brake regen, voltage/power is applied from the batt pack to the coils so a magnetic field is present and therefore generates power to deliver to the batt pack. Lenz Law is the braking effect you feel. BUT as the generator rpm decelerates so does power production and at some point, Voltage will be less than the batt pack and the regen power is useless because in order for current to flow into the batt pack you MUST have a higher voltage applied. Sure you can apply more power into the coils but that will pull from the batt pack. As you increase power to the coils, there is an intersect point where kenetic energy rpm is insufficient for power production and it’s a negative hit on the batt pack.
    I theorize that somewhere between 25-15mph brake regen is useless and if it is used for anything, it is used to be shunted to ground to keep the Lenz laww effect of braking then the mechanical brakes kick in.  

    That would be basically true with an induction motor excited at a constant frequency, but with a synchronous motor and an intelligent power converter (which I am pretty sure that the Volt has), you can reduce the field frequency as the rotational speed decreases to always keep the motor leading the inverter by a few degrees, thus acting as a generator all the way to almost zero speed. The amount of regenerative braking will be a function of how far the motor leads the inverter, and not the vehicle speed. Presumably, the lead angle will be proportional to the difference between the accelerator pedal position and the actual vehicle speed, so the more you let up, the harder the car will regenerate/decelerate. I don’t see why efficiencies of up to 80% couldn’t be achieved this way, but others claim it is far less in reality, so I’d like to see more data on this.


  126. 126
    Dan Petit

     

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    Dec 4th, 2009 (8:09 pm)

    Was GM going to announce a song related to Volt today?


  127. 127
    Geronimo

     

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    Dec 4th, 2009 (8:11 pm)

    The drag force on a car is given by the equation:
    b697885f182aeb644f68ffc494101dff.png

    It’s proportional to the density of air (the p), the square of the relative speed between the car and the air (v^2) and the Coefficient of Drag times the frontal area A.
    (Actually, Cd is a function of speed, not a constant, but never mind that for now…
    p is also not a constant – air density goes down as you drive up a mountain…)

    But of interest is the A:
    what is the frontal area of the Chevy Volt ?

    The GM EV1 had a frontal area of 3.95 sq ft (1996)
    The Toyota Prius had an A of 6.24 sq ft (2004)
    The Chevy Corvette had an A of 6.27 sq ft (1992)
    The Hummer H2 had an A of 26.5 sq ft (2003)

    http://en.wikipedia.org/wiki/Automobile_drag_coefficient#CdA


  128. 128
    Herm

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    Dec 4th, 2009 (8:36 pm)

    Todd: I think you need to check this out. I went to the Toyota site and put in all the features that come on the Volt. The total for the Hybrid Prius – $34,798.00.  

    There are lot of crazy features on the high end Prius that are not available on the Volt.. automatic parking, predictive cruise control, automatic lane centering steering, and automatic pre-collision brakes. Not that I would want any of them..


  129. 129
    Red HHR

     

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    Dec 4th, 2009 (8:43 pm)

    Jim I: So lets make a Voltec Mini ‘Vette!! It is fiberglass, so it is saving weight. It should be a smaller version, so as not to compete directly with or hurt the mystique of an ICE based Corvette. It would have great torque. I am thinking about the size of a Solstice. And as a two seater, that same 16 KW/Hr battery pack should actually get a better AER.
    It would make us sports car types very happy!!
    If I have to wait another two or three years, I might as well get what I really want………………….

    If the new GM could make low volume car profitable, I would suggest the “Pebble Beach Series” that would be a modern interpretation of Best In Show. Kind of like the HHR except more exclusive. They could be BEV or Voltec, priced right and collectible.

    I do not know what the Cd is, but it looks very aerodynamic…
    horch-s.jpg


  130. 130
    Dave K.

     

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    Dec 4th, 2009 (8:47 pm)

    Dan Petit: Was GM going to announce a song related to Volt today?

    Yes, the tune is about a minute long and plays off the letters V-O-L-T.

    The Converj 12/04/09.

    Converj%20LA-02.jpg

    =D~


  131. 131
    Dave K.

     

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    Dec 4th, 2009 (8:55 pm)

    The ever popular Volt girl. She said a drive to the grocery store and the gym will use no gas at all. You got to love that.

    Volt%20LA%2008%20girl.jpg

    =D~


  132. 132
    Dave K.

     

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    Dec 4th, 2009 (9:05 pm)

    The Volt motor compartment. Notice the ample cooling.

    Volt%20motor%20compartment%2012-04-09.jpg

    =D~


  133. 133
    Dan Petit

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    Dec 4th, 2009 (9:16 pm)

    Bob G:
    That would be basically true with an induction motor excited at a constant frequency, but with a synchronous motor and an intelligent power converter (which I am pretty sure that the Volt has), you can reduce the field frequency as the rotational speed decreases to always keep the motor leading the inverter by a few degrees, thus acting as a generator all the way to almost zero speed.The amount of regenerative braking will be a function of how far the motor leads the inverter, and not the vehicle speed.Presumably, the lead angle will be proportional to the difference between the accelerator pedal position and the actual vehicle speed, so the more you let up, the harder the car will regenerate/decelerate.I don’t see why efficiencies of up to 80% couldn’t be achieved this way, but others claim it is far less in reality, so I’d like to see more data on this.  

    It’s my understanding that regen efficiencies can recover energy to as low as three miles per hour. A hybrid engineer revealed that to me about three years ago at the Renewable Energy Roundup (lots of EV’s) in Texas.
    That suggests that the blended braking has the pads lasting about 200,000 miles,or, the life of the vehicle.

    Since I had studied the wear factors on an 03 Hybrid with 135,000 miles to have 35% of the pad thickness still available, then, it would not at all surprise me that technology has advanced to the extent that for regular breaking rates of deceleration, an even greater than 97% kinetic energy distance is recoverable at whatever the combined inefficiency losses are subtracted from that 97%. This brake pad wear reduction was repeatedly confirmed by reliable sources in the subsequent years.


  134. 134
    Dan Petit

     

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    Dec 4th, 2009 (9:35 pm)

    Hey Dave K,

    Thanks for the new picture. (I just got captivated again. LOL).
    (You had to do that, didn’t you? LOL)

    Bob said that there were 5 heat exchangers. There is another one that can not be seen in front of the three that are located in the area where the radiator is. (Which one is the radiator? lol).

    My guesses.
    The engine radiator is in back.
    Either a pack AC or Cabin AC condenser in the middle,
    Either a Cabin AC or pack AC condenser in the front,
    Maybe a traction motor heat exchanger is lower in front unseen in the pic,
    Possibly the controller/inverter heat exchanger or a heat sink for enclosed electronics in the foreground in front of the left front tire.

    There might be three phase cables in orange (bundled, so that they appear as a single orange image that tapers to differentiate as they go upwards.
    Then, what seems to be pink cables or hoses(?) could be Dexcool cooling lines for the Inverter/controller cooler. (But they also could be heavy electrical cables, or sets of bundled wires). There might be several other Dexcool cooling lines for another purpose.

    Most folks have fun with the style. No surprise that I get captivated with technology instead. (lol)
    Fun picture. Thanks. Made my day.
    Dan.


  135. 135
    jeffhre

     

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    Dec 4th, 2009 (10:47 pm)

    Dave K.: The ever popular Volt girl. She said a drive to the grocery store and the gym will use no gas at all. You got to love that.

    What time did you go? I was there about 1pm. The “Volt Girl” Tricia, put up someones zip code and showed a 20 mile radius to illustrate where he could drive all electric. I didn’t get to hear the Volt song though.

    Volt looks better in person than pics. Hey Static the color your favorite) looks a lot better in person too. Well networks going down so NPNS…


  136. 136
    Dave K.

     

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    Dec 5th, 2009 (12:22 am)

    hi jeffhre… left the GM display around 12:45 and checked Fisker and Porsche. The singers performed The Chevy Volt Song just after noon.

    Here’s the Cruze in Viridian Joule.

    Cruze%20VJ%20LA%2009.jpg

    Cruze%20LA%2009%202.jpg

    =D~


  137. 137
    Matthew B

     

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    Dec 5th, 2009 (12:46 am)

    Bob G:
    That would be basically true with an induction motor excited at a constant frequency, but with a synchronous motor and an intelligent power converter (which I am pretty sure that the Volt has), you can reduce the field frequency as the rotational speed decreases to always keep the motor leading the inverter by a few degrees, thus acting as a generator all the way to almost zero speed.The amount of regenerative braking will be a function of how far the motor leads the inverter, and not the vehicle speed.Presumably, the lead angle will be proportional to the difference between the accelerator pedal position and the actual vehicle speed, so the more you let up, the harder the car will regenerate/decelerate.I don’t see why efficiencies of up to 80% couldn’t be achieved this way, but others claim it is far less in reality, so I’d like to see more data on this.  

    Thanks for already putting up the bulk of what I was going to say!

    I would also comment that the inverter operating as a controlled rectifier boosts the motor voltage up to the pack voltage. This is done by shorting the motor windings each switch cycle and then “kicking” the current into the battery using the inductance of the motor windings. At some point the motor will no longer be able to generate as much as the losses of the motor and inverter, but this should be very low in speed, maybe around 3-5 MPH.


  138. 138
    stas peterson

     

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    Dec 5th, 2009 (3:58 am)

    If Congress classified th Aptera as a car then its DEAD. It may be dead anyway as Aptera has shown no symptoms of having Any money.

    Classified as a “covered motorcycle” , it didn’t have to conform to the safety regs, like crash ratings, headlights, seat belts, airbags, roll over strength, ECS, ABS, air bags Chmsl, Yadda, Yadda, Yadda. As a car it now does…


  139. 139
    koz

     

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    Dec 5th, 2009 (4:46 am)

    Dave K.: hi jeffhre… left the GM display around 12:45 and checked Fisker and Porsche. The singers performed The Chevy Volt Song just after noon.Here’s the Cruze in Viridian Joule.=D~  (Quote)

    Looks more like Chalcedony Joule


  140. 140
    Dan Petit

     

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    Dec 5th, 2009 (8:13 am)

    Blind Guy: The under side of these new cars is getting much smoother, so I am willing to give upsome air drag for more ground clearance so our front bumper won’t drag leaveing our driveway.My wife is careful but our Prius has a 6 inch crack from dragging and I really don’t want that to happen again.  

    Entering the steep right-of-way of a driveway at a 45 degree approach angle if the situation permits might help. I have a friend with an 03 Corvette that has to do that, but, you also have to make sure the tire pressure is at the allowable/comfortable high end of the acceptable pressure range to assure that highest (extra) one-half to one inch original specification clearance. Loosing that one half inch height to a pressure loss would add lots of rolling resistance too, as we all are aware.


  141. 141
    Dave K.

     

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    Dec 5th, 2009 (9:54 am)

    koz: Looks more like Chalcedony Joule

    Transformer Arc Plasma should have won the signature color contest.

    Cruze%20LA%20tail.jpg

    =D~


  142. 142
    nasaman

     

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    Dec 5th, 2009 (10:18 am)

    Dave K.: Transformer Arc Plasma should have won the signature color contest. =D~  (Quote)

    I still like my entry, “Liquid Lithium”, ’cause it’s so slippery the Cd would drop to 0.25! ;)


  143. 143
    Dave K.

     

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    Dec 5th, 2009 (10:35 am)

    nasaman: I still like my entry, “Liquid Lithium”

    The Converj will look fine in Black Cherry or Midnight Purple.

    Converj%20LA%20front.jpg

    =D~


  144. 144
    carcus1

     

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    Dec 5th, 2009 (10:35 am)

    nasaman:
    I still like my entry, “Liquid Lithium”, ’cause it’s so slippery the Cd would drop to 0.25!   

    Liquid Lithium
    Lithium (Eskalith®, Eskalith CR®, Lithobid®) is a medicine often used for controlling the symptoms of bipolar disorder. It comes in several different forms and is available by prescription only
    http://bipolar-disorder.emedtv.com/lithium/liquid-lithium.html

    Marketing might (or might not) have a problem with that one, depending on their mood(s).


  145. 145
    Roy

     

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    Dec 5th, 2009 (6:57 pm)

    loboc: They can do better:http://www.electrifyingtimes.com/gmprecept.htmlThe Dodge Intrepid (I have one!) is very good as well.http://en.wikipedia.org/wiki/Automobile_drag_coefficient  (Quote)

    Wow, GM was working with Lithium-polymer batteries for the EV1 back in 2000. I think that’s about the time I first heard of lithium-polymer batteries as a new lab discovery.


  146. 146
    koz

     

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    Dec 7th, 2009 (2:54 am)

    Interesting video of Martin Eberhard speaking with Bob Boniface at the LA Auto Show about Volt’s aero. I wish the audio was a little better.

    http://www.mefeedia.com/watch/26252381


  147. 147
    Dr. Ibringdoh

     

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    Dec 7th, 2009 (9:44 am)

    Loboc: As it is currently done (ie. hand lay-up or chopper gun), fiberglass is not very good for structure. You need steel or wood or another ’stiffener’ in the lay-up to make it strong. Which also makes it heavier.Yeah, as i mentioned, advanced molding processes and materials not currently used for boats or cars (and more expensive like carbon-fiber) could make this better. It’s just not economically feasible right now. How many cars do you see made of fiberglass? Mostly it’s plastics like PVC.And I never said fiberglass was a poor impact material. It just breaks apart instead of bending to absorb the energy. My point was that after impact, you have a real mess with fiberglass.  (Quote)

    Respectfully, you don’t know what you are talking about. Pultrusion isn’t hand lay-up, nor is sheet molding compound (SMC).

    Try reading the links I supplied before commenting.

    Dr. Ibringdoh


  148. 148
    Dr. Ibringdoh

     

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    Dec 7th, 2009 (9:47 am)

    Nelson: Ibring

    A car doesn’t only move through air, it drags itself on pavement. I’m thinking a cars COD should take into account the COF (coefficient of friction) as well.

    Excellent point!

    Respectfully,

    Dr. Ibringdoh


  149. 149
    steel

     

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    Dec 7th, 2009 (5:25 pm)

    On Cd

    Airdynamic surface quality has a definate effect on Cd. It can control the size and quality of the boundry layer. (Transition between free flowing air and non-moving air attached to the surface of the car).

    In practice, all surfaces will be painted and the paints quality will matter more than Steel/Aluminium/Fiber Glass/Carbon Fiber.

    Dimples can help in some ways (another poster mented one way, attached turblent boundry layer instead of disattached turblent boundry layer). Yet a car has an issue in that during testing it typically goes over a -wide- speed range. Some dimples that help at 60 mph, might hurt at 40 and 70. I think no Engineering department has been able to overcome the negative impulse of the look with comparable increase in mpg. (I’d drive a dimpled Prius that got 60-70 MPG compared to 50 MPG. But Dimples might get to 55….)

    2.
    Coefficient of Rolling Resistence is constant in relation to speed etc.

    Drag= CoRR * Mass + CoAR * v^2 * rho * A/2

    Its pretty hard to combine CoRR and CoAR (Cd)


  150. 150
    Don J

     

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    Dec 7th, 2009 (11:34 pm)

    Well done, GM. Well done.

    Coefficient of Friction? Uh, the Volt does have wheels. I think rolling resistance is the term you are looking for.

    Of course the Prius with its little 15″ wheels would probably win that.


  151. 151
    Wowlfie

     

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    Dec 11th, 2009 (5:23 pm)

    Toyota was probably passing wind that’s why the 0.25 number came in so low!


  152. 152
    Steve

     

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    Dec 24th, 2009 (8:23 pm)

    Neutron Flux: Thats nice but that car recently back to the drawing board for an almost complete redesign to improve structural integrity etc. Not sure it will be on the street before the Volt, in production mode I heard they are waiting on those ultra capacitors from that unnamed company (LOL). OK for commuter car but won’t work for families with seating for 2. Nice if you can afford a limited use vehicle. Entry / exit still looks a bit difficult even after redesigning. I’d suggest trying before buying.  (Quote)

    Apterra is neat and all, but it’s a two seater, not in production yet either and initially only available in CA. They’ve completely changed the dirve system since the prototype. Now it’s front wheel drive. If it fit my needs and wasn’t on the opposite coast, I might be more interrested.


  153. 153
    Steve

     

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    Dec 24th, 2009 (8:32 pm)

    Neutron Flux: Thats nice but that car recently back to the drawing board for an almost complete redesign to improve structural integrity etc. Not sure it will be on the street before the Volt, in production mode I heard they are waiting on those ultra capacitors from that unnamed company (LOL). OK for commuter car but won’t work for families with seating for 2. Nice if you can afford a limited use vehicle. Entry / exit still looks a bit difficult even after redesigning. I’d suggest trying before buying.  (Quote)

    Apterra is neat and all, but it’s a two seater, not in production yet either and initially only available in CA. They’ve completely changed the dirve system since th

    Dr. Ibringdoh: Excellent point!Respectfully,Dr. Ibringdoh  (Quote)

    e prototype. Now it’s front wheel drive. If it fit my needs and wasn’t on the opposite coast, I might be more interrested.