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Volt engineers need to consider weight

13K views 30 replies 23 participants last post by  llninja 
#1 ·
Love the car. New owner. It seems to me some parts of the car are odd in their overly heavy design. With a car such as this I'm surprised there wasn't more effort to save weight. I understand the cost implications of interchangeable parts with other vehicles but there are some missed opportunities.

First example, this whale of a key fob they gave me. Sure, the key fob is probably perfect for a look at me type person driving a tahoe where everything bigger is better, but I like light and streamlined, if not downright stealthy. I always make sure I only have one key fob with me at a time, probably gets me a couple more miles of range. I took it apart and I'm fully convinced the thing can be much smaller and lighter.

In fact, I don't even need the buttons off it, just the circuit board and the battery. Maybe I'll figure out a way to make my own enclosure. Yeah yeah, I know, what if the battery dies or something.

The hatch door is huge and heavy, the wheels are nothing special either. How about using plastic body panels? They have the technology from Saturn and they worked pretty well I thought.

Any other ideas where GM can easily save some weight and improve this car? Did they make more effort to save weight in the Bolt does anyone know?

Am I off my rocker with this observation?
 
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#2 ·
Personally I wouldn't want a cheapened up rattle tinty econobox which is what you are describing. That 700 pound battery planted smack in the center of the car, and as low as it can be placed is one huge item which results in such a stable quiet, great handling car. Drive or ride in a Prius to compare.
 
#3 ·
I could come up with about a dozen ways to reduce weight on the Volt without even trying, however it would both make it less comfortable, dare I say less luxurious, and would also probably pump the cost up about 10-15%
 
#7 · (Edited)
My guess is the engineers did the best they could for weight reduction given all the constraints they had to work with.

I wonder if the OP even knows the hood is aluminum or the wheels are on the light side for OEM. Really the weight of the key fob is important? A trip to the bathroom or emptying the change out of your pocket would likely be a bigger weight reduction. Lightness costs money and while important, the aerodynamics are probably more important as regenerative braking somewhat compensates for the weight.

By the way, that bulky key fob has about a 200 foot range. A smaller, lighter one would likely have less range, battery life or both.
 
#8 ·
Yes, I'm so sorry to hear that you fell off your rocker. I hope the injuries weren't too serious. But next time it might be best to wear a helmet.
 
#11 · (Edited)
Agreed, the OP is off their rocker. The weight of the fob is going to save maybe 1/3rd of an inch of range compared to the weight of the rest of the car. If the OP drove around naked, they could shave many more pounds than the keyfob. Or how about pitching the owner's manual, carpeting, rear center console (gen 1), tire pump, interior upholstery, unused seats.

Better yet, just cut back on hohos and twinkles...:)

Only I wish GM didn't skimp on was the cargo cover - I ended up adding a lot of weight buying a voltshelf which is made out of plywood and carpeting. Had they built a proper one with plastic and fuzzy stuff, I would have actually saved me weight and money, but I don't mind giving Scarlett money as he is a good ol' American trying to live the American dream. I then proceeded to add a weather tech cargo liner and 18 inch wheels and tires which dinged my range even more. So that slimfast keyfob idea is like picking your nose and flicking it into an ocean, it's not going to make any difference with the environment.
 
#9 ·
One of the things that makes volt seem like a premium vehicle is the doors that feel heavy and give a satisfying sound as they close. Instantly gives a better impression of quality over other vehicles with lighter doors - they just feel cheap.
Take that away and you're in a rattly tin can.
Sure, you gained 2 miles. But you lost 20% of sales!

I don't find the fob that large at all.
I know people with wallets twice as thick.
 
#12 ·
Sure, the car is 500 lbs heavier than other cars its size. But I have to believe that extra weight is also, as a result of basic physics, one of the reasons it received this:

http://www.iihs.org/iihs/news/desktopnews/2017-chevrolet-volt-earns-top-safety-pick-award

The traction battery alone is 400 lbs or so, and I think removing 400 lbs from the rest of the car to offset this and get it closer to other cars its size would result in either a cost premium, or a sacrifice in safety, that I'm not sure I would want. I like the solid feel of the car and I think the GM engineers did a nice job of balancing efficiency and strength in the overall car.
 
#13 ·
I'm surprised there wasn't more effort to save weight.

First example, this whale of a key fob they gave me.

The hatch door is huge and heavy, the wheels are nothing special either. How about using plastic body panels?
As others point out, the key fob is not something I'd dwell on.

The hatch uses light aluminum, what's your solution, carbon fiber? What are the resulting trade-offs besides adding more expense?

The wheels are also aluminum, on the light side of weight. Your solution would be what, special racing wheels? What are the resulting trade-offs besides adding more expense?

No doubt they could use lots more aluminum, carbon fiber, magnesium and composites, throw out the sound deadening material, take out three seats, replace all the window glass with plastic, make the car smaller. But be aware there are negative offsets in style, comfort, price.

Cars are always a compromise. among competing goals. Weight reduction is just one goal, not the only one.
 
#14 ·
Personally, I love the weight of the vehicle. On my recent trip home to visit the family I had an opportunity to drive down a very hilly curvy road, that I have hated driving in all of my previous vehicles I have owned, except for 1.

My first car when I turned 16 was a '87 Mazda RX-7 Turbo II. I would fly down this particular state highway in rural Missouri at 80+ mph with a huge smile as I went through its perfectly banked curves. Unfortunately 'Rex' caught fire in the parking lot of my school my junior year, so his time making me grin was short lived.

This year, with Gizmo in sport mode and no pets or spouse in the car, I relived my childhood love of this road going to my grandparents house, and Gizmo handled and performed much better than I could have ever expected, and I arrived at my destination with a huge smile on my face.

TL;DR: If you want a cheap car made of plastic that rattles constantly and handles like a Little Tikes car, buy an old Saturn or a Smart Car from Ebay or Craigslist and sell your Volt to someone who will appreciate it!
 
#15 ·
Had a Saturn L we bought new and ran for almost 300k miles. The plastic door skins and front fenders cost GM more than metal, and many folks disliked the huge body gaps necessary because the plastic expands in hot weather. Did you know the Volt transmission (gen 1) weighs over 400 pounds? Almost as much as the battery. Lot of heavy magnets in there. Volt's wheels feel feather-weight compared to the steel wheels on our Camry. The aluminum hood is light too, and much more expensive than a steel one. GM got pretty nit-picky with aerodynamics on the gen 1, but it does make a difference. I feel the car is a nice balance of weight vs solid feel and good handling. And yes, I've found Hal can do some pretty impressive cornering when pushed a bit. Key fob? Come on. The gold in my teeth weighs more. I love the switchblade key!
 
#16 · (Edited)
I'm sure the OP is being facetious. Actually that's a great point especially from any early adopter perspective (aka old men with money, or tech money, etc).

I agree I bet there is excess weight that can be found, and I'm sure the aftermarket community will find more to shave down. I think they did a great job with this car making it the perfect ratio of "lux to economy". My car is a 2012 that was sold @ 44K I picked it up @ 12K CPO !!!

From my point of view, I bought this vehicle secondhand as a CPO. My first ever vehicle without shifting gears manually and my first car with a Fob. Also my first to maintain a 105 MPG average driving in this winter hell. I feel they clearly lightened up the car as much as the bean counting would allow, and maintain CAFE, and all that during the whole you know bailout/bankruptcy thing.

I for-see the next gen of GM's approach to fuel economy compliance as a Chevy fleet based econo-priced Volt\Bolt CA/NY only base model (like a Bob Lutz Viamotors fleet special powertrains based on the Volt), the current Chevy Volt consumer level and possibly a Buick or Caddy Lux volt? (Four-door ELR?). Either all this on its own model line (like the Prii) or possibly thee technology spread across GMs various corporate parent brands.

TLDR GM done good compared to 2009. Less Fed regulations after 2017 with the current political climate means probably less all-50 state availability and more state specific compliance, for example a Fleet VOLT specifically for CA/NY etc Where as the base and premium edition as presented as of the 2017 model year etc. Fleet probably reduced weight as not having heated seats, steelies? etc

Sidenote, I've seen three or four Volts in Sao Paulo Brazil, and one Opel Ampra!~ Viva Brazil!
 
#17 ·
One of the big features GM touted for the Gen 2 Volt was significant weight reduction. Dispute being larger and faster the GM engineers were able to knock of around 250 pounds (3800 vs 3550 pounds).

GM like most other automobile manufactures implement a system engineering approach. In the GM approach each major design area is given a target weight reduction. Each week the engineers have to report progress in meeting design requirements including weight in grams over or under their assigned weight. If a weight reduction greater than required is realized, that reduction is flowed to other areas like suspension and structure so that they can redesign for lower weight. This process has resulted in their GM vehicles equal to or better than their competitors in term of weight, which translates into improved performance and fuel economy. Of course there may be other areas in which weight could be reduced but I woud be surprised if these haven't already been given close scrunity by GM engineers.
 
#19 ·
Yes, it really is a pain when my wife pumps the seat all the way up and I pump the seat all the way down to get my 6'3" frame into the tiny volt. If course with my next vehicle, I'm aiming for a huge weight gain (Suburban or model S).
 
#22 ·
I drove two lighter hybrids for 140K miles. Of course, they had much smaller batteries, were tinny and prone to rattles, and were noisy. They also weren't very comfortable. I'm talking about the Prius.

Of course, I'd love a lighter Volt, but one that has all the qualities of my 2017. Unfortunately, it's a question of cost and such a car would probably sell for two or three times the price of mine.
 
#25 ·
I beg to differ. Someday we will have vehicles with an electric motor, a Mr. Fusion, and a buffer battery smaller than the volt's battery to allow Mr. Fusion to spin up and down. That will definitely be lighter than a comparable ICE or BEV.
 
#26 ·
#27 · (Edited)
Wow, it's in St. Louis. Road trip!!!

Now if they would only make a drop in AWD EV kit for my CTS, I'll be set
 
#29 ·
I was of course being facetious about the fob, although I do hate it. What about the shifter mechanism? Very solidly built, feels great. Probably is completely fake though. Why would there need to be any mechanical shifting going on, it is all switches and solenoids I would expect.

I can verify that the seats are pretty light, I removed the driver seat in a failed attempt to modify it (I chickened out and put it back in).

I guess my overall point is that the designers seemed to worry more about making this look and function like a traditional car instead of taking advantage of the fact that it isn't. Their audience, based on what I've read here, aren't traditional people.
 
#31 ·
I think the volt engineers did a better job of balancing a great car vs. weight. Just test drive a Prius and you'll find engineers who went overboard...the car drives like a tin can with anemic acceleration, all on the name of fuel efficiency. Yet for most people, the volt will blow away a Prius in fuel economy.
 
#30 ·
Ok, I'm not thinking about this correctly. I'm now convinced the weight barely matters. Yes, it makes the batteries work harder accelerating and going up hills, but it doesn't affect the battery usage while cruising as it only has to overcome friction and wind resistance. What it does do, if we use regenerative braking almost exclusively, is put more regen back into the batteries when coasting downhill or regen braking. Since efficiency of the electricity is in the high 90's for both output and recharge, the average sum of the cost and benefit of the weight is pretty minimal.

Maybe I can keep using the key fob.
 
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