GM VVT Motors

[gtx28]

Has anyone heard anything about a vvt motor or Variable Valve timing motor for the Vette, im not talking about a dohc, but a ohv vvt motor, where they want to turn cylinders off like the old lincolns or caddys i cant remember the 8-6-4 motors are what im talkin about. I heard they want to bring this back for fuel economy. Any one have some input??

[RC45]

Why? We already get 25mpg+ if we use 6th gear.

If we wanted economy we would by Civics.

Remember the Vette is the only current super performance car for sale in the USA that does not have a gas-guzzler tax...

[nthfinity]

ive heard stories back home of a guy who works at the GM proving grounds in Milford MI , he says the Corvette Z series will be running a Variable Valve system in the new motor... its also expected to push 500+hp, and im sure a similar torque figure. Just roumers right now. i dont think they will be arriving at least until half way through 2006.

[RC45]

Sure - VVT is ok for performance - but why fuck around with some "economy 4-6-8" variable cylinder crap... ?

[Nocturn]

Im pretty sure hes talking about the DOD (displacment on demand) feature that shuts down 1/2 the cylidners when they aren't needed.

[T-Bird]

well DOD seems to work pretty damn well for Chrysler on the new Hemi it's so good you don't even notice it.

[Nocturn]

Yes but im wondeirng what it will sound like on cars with modified exhaust systems.

[RC45]

Originally Posted by T-Bird well DOD seems to work pretty damn well for Chrysler on the new Hemi it's so good you don't even notice it.

Who gives a shit? That is a large luxo-sedan.

Displacement on demand is a stupid discussion point when high performance cars are on the agenda.

If I wanted 4 cylinders I would buy a Civic.

If I wanted fuel economy I would buy a Civic.

If I wanted HP/l I would buy a Civic.

Technology for the sake of technology is a pretty pointless endeavour.

Form should follow function.

[Nocturn]

True but it might also save certain engine from having the gas guzzler tax while retaining its performance. It's not exactly hurting anything either.

[nthfinity]

well, if the gas guzzler tax is 1000$ usd, and 20,000 vehicles are sold per year, that is a ripe 2,000,000 $ spent on gas guzzling....

however, the money spent in developing and researching such an engine would far exceed this cost, which in the end would come down to the costomer paying for it anyway, weather much more, or a little more. i would tend to assume much more as even slightly modifying an exisiting platform costs in the multi-millions.

just thought id point that out :roll:

[SilverPhoenix]

I read something like this, something about advanced Cam Phasing, which puts the efficiency of it's variable cam changing to within 80% of DOHC engines.

[Nocturn]

Originally Posted by nthfinity well, if the gas guzzler tax is 1000$ usd, and 20,000 vehicles are sold per year, that is a ripe 2,000,000 $ spent on gas guzzling.... however, the money spent in developing and researching such an engine would far exceed this cost, which in the end would come down to the costomer paying for it anyway, weather much more, or a little more. i would tend to assume much more as even slightly modifying an exisiting platform costs in the multi-millions. just thought id point that out :roll:

It's not a drastic change, just a clever addition to some computer work and the spark and fuel don't go to 1/2 the cylinders. Not like their adding on 2 more doors or something like that.

[RC45]

Originally Posted by Nocturn Originally Posted by nthfinity well, if the gas guzzler tax is 1000$ usd, and 20,000 vehicles are sold per year, that is a ripe 2,000,000 $ spent on gas guzzling.... however, the money spent in developing and researching such an engine would far exceed this cost, which in the end would come down to the costomer paying for it anyway, weather much more, or a little more. i would tend to assume much more as even slightly modifying an exisiting platform costs in the multi-millions. just thought id point that out :roll: It's not a drastic change, just a clever addition to some computer work and the spark and fuel don't go to 1/2 the cylinders. Not like their adding on 2 more doors or something like that.

I think you are dramatically under-estimating the complexity of succesfully and graciously killing 2 or more cylinders under load - and then firing them right back up like nothing happened...

[nthfinity]

Originally Posted by RC45 Originally Posted by Nocturn Originally Posted by nthfinity well, if the gas guzzler tax is 1000$ usd, and 20,000 vehicles are sold per year, that is a ripe 2,000,000 $ spent on gas guzzling.... however, the money spent in developing and researching such an engine would far exceed this cost, which in the end would come down to the costomer paying for it anyway, weather much more, or a little more. i would tend to assume much more as even slightly modifying an exisiting platform costs in the multi-millions. just thought id point that out :roll: It's not a drastic change, just a clever addition to some computer work and the spark and fuel don't go to 1/2 the cylinders. Not like their adding on 2 more doors or something like that. I think you are dramatically under-estimating the complexity of succesfully and graciously killing 2 or more cylinders under load - and then firing them right back up like nothing happened...

its more then a drastic underestimation; its a very very different process required to perform this seemingly simple task? its so complex, im sure i dont know half of what would go into it separte from a normal motor, i could name easily 9 or 10 severely different items id hope GM, as well as the rest of the auto manufacturers shy away from this awful technology

[gtx28]

I un like some dont mind this, i mean what is wrong with better fuel economy. Nothing in my oppinion, so long as it does not compromise performance. I am just curious to see what gm can come up with.