Lentz
03-20-2008, 08:22 PM
Really happy GM is making this car. Hope to see it as a sporty Caddy.
That means light weight and good handling and a Prius sized car, but not ugly like a Prius. The show car looked great!
Love the engineering. Only one transmission hookup since the engine only drives the alternator and a very efficient engine since cams, turbo and compression ratio can be tuned for nearly constant RPM. A far cry from all of the monkey motion in the Prius.
I'm gonna put in 30 degree valve seats, port match everything and add a low back pressure system after the turbo. All that should increase the efficiency as well as the go, for all you greenies. If the cams were optimized for 30 degree seats the exhaust valves could be held closed until a little closer to BDC increasing the enegy tranferred to the piston. Everything else decreases the pressure drop on the intake side and increases it accross the turbo.
Hope you experiment with the 30 degree valve seat thing. Low lift flow goes way up because the aperture increases more rapidly with a 30 degree seat than a 45 degree. They equalize at valve lift equal to about 25% of the valve diameter, at which point the valve diameter and not aperture starts limiting the flow. This would mainly be useful on the exhaust side. You could still make the seat very wide for durability and not lose a lot of flow across a wide seat because of the high pressure differential.
Offer a couple of electric motor options when you get time but plan for it by making the cables big enough to handle the extra amps. it would be nice if us hot rodders could just bolt one it.
If any engineers read this, make my day and write me. I'm an ME as well as a CPA.
That means light weight and good handling and a Prius sized car, but not ugly like a Prius. The show car looked great!
Love the engineering. Only one transmission hookup since the engine only drives the alternator and a very efficient engine since cams, turbo and compression ratio can be tuned for nearly constant RPM. A far cry from all of the monkey motion in the Prius.
I'm gonna put in 30 degree valve seats, port match everything and add a low back pressure system after the turbo. All that should increase the efficiency as well as the go, for all you greenies. If the cams were optimized for 30 degree seats the exhaust valves could be held closed until a little closer to BDC increasing the enegy tranferred to the piston. Everything else decreases the pressure drop on the intake side and increases it accross the turbo.
Hope you experiment with the 30 degree valve seat thing. Low lift flow goes way up because the aperture increases more rapidly with a 30 degree seat than a 45 degree. They equalize at valve lift equal to about 25% of the valve diameter, at which point the valve diameter and not aperture starts limiting the flow. This would mainly be useful on the exhaust side. You could still make the seat very wide for durability and not lose a lot of flow across a wide seat because of the high pressure differential.
Offer a couple of electric motor options when you get time but plan for it by making the cables big enough to handle the extra amps. it would be nice if us hot rodders could just bolt one it.
If any engineers read this, make my day and write me. I'm an ME as well as a CPA.