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... :D

[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]

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]

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]

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]

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.

[graywolf624]

id hope GM, as well as the rest of the auto manufacturers shy away from this awful technology

I disagree. Only from the stand point that dod might be the only thing that saves the corvette. Current talks of raising cafe standards(see that felching dick weasel kerry) could potentially ruin the vette as a performance option. So while in the short run I don't see the necesssity. Protecting the future by developing technologies that can be used later in such occurances.. I think they are on the right track.

For the same reason I think they would be fools to ignore this type of technology and hybrids. Does that mean it will work? Who knows? Should it be first introduced in a vette? who knows? It certainly should be used in a car though.

[nthfinity]

For the same reason I think they would be fools to ignore this type of technology and hybrids. Does that mean it will work? Who knows? Should it be first introduced in a vette? who knows? It certainly should be used in a car though

this is an interesting point. i agree that hybrid technology is far from a bad thing for the auto industry, i just cant see it being a performance option. i do however strongly believe that H2 as a fuel source is the future of performance vehicles... time will tell. i know FoMoCo has been researching Hydrogen more extensively, and in conjuntion with a few universities. current technologies show hydrogen running between the 40% and 60% efficiancy ratings--- far beyond that of conventional foscil fuels. the blue oval has stated to its engineers that they may not have to, but it is thier responsibility to evolv this change into reality.

[number77]

are you talking about a camless engine? there are many rumors about 3-valve heads. there also have been rumors about the more exotic technologies. some of those include a camless engine, dual rotor brakes, and some alloy block.

[T-Bird]

why would there be rumors about 3-Valve heads? they're available already in Ford motors just like 4 and even 5 with Audi! And no they are not Camless they just shut off the lifters.

[number77]

why would there be rumors about 3-Valve heads? they're available already in Ford motors just like 4 and even 5 with Audi! And no they are not Camless they just shut off the lifters.
well, you can't take heads off of those and put them on an ls1-2
those cars use overhead cams. there are cars with 3-4 valve heads with daul overhead cams and what not. the ls2 is also bigger than the others and is a pushrod motor.

[Nocturn]

A camless engine uses actuators to push/pull open the valves, GM experimented with this but has said they weren't going to use it because it had reliability issues or something to that extent.

Mayhap I am overestimating Dod, but tell me what all is involved in shutting down the cylinders, fuel and spark being cut out is all computer controlled, so where in is the complexity, the valves will still open but no fuel will be delivered, and no spark will ignite. Seems simple to me, but I could be overlooking something.

[RC45]

Only from the stand point that dod might be the only thing that saves the corvette. Current talks of raising cafe standards(see that felching dick weasel kerry) could potentially ruin the vette as a performance option.

Nonsense - it will simply mean the Vette will no longer be the "poor mans super car" and be priced to reflect the vastly reduced produciton numbers, increased performance and extra taxes that making it a Viper price-bracket machine will do... ;)

With sedans already pushing 500hp+ and 0-60 in 4 and 5 seconds, - why would only the Vette be at risk?

Most other hyper/super/fast cars suck gas like a cheap hooker... and face no more restrictions than the Vette.

Kerry is stupid dumbass if he thinks that "Laws" can scare profit away... the insurance industry has more chance of reining in cars performance than any group of tree-hugging liberals... ;)

[graywolf624]

With sedans already pushing 500hp+ and 0-60 in 4 and 5 seconds, - why would only the Vette be at risk?

Most other hyper/super/fast cars suck gas like a cheap hooker... and face no more restrictions than the Vette.

I think you missed the point. I am pointing to a situation similar to what happened between 75-82, albeit instead of due to gas prices, very possibly influenced by cafe. This fear has been reflected to me by several upper level gm executives(that the corvette and cars like it may get snuffed out by this jackassery). It would effect all performance vehicles. The point is that hopefully all manufacturers involved are thinking enough ahead to side step such problems. The environmentalists are the fear. In fact.. insurance companies are little to no fear with the vette. Vette insurance is alot lower then the corresponding camaro, mustang, ect insurance because of the ownership demographic.


Kerry is stupid dumbass if he thinks that "Laws" can scare profit away... the insurance industry has more chance of reining in cars performance than any group of tree-hugging liberals...

You must not have been in the US when catalytic converters and cafe first got enacted. Performance cars from 1976-1982 are not just jokes because no one could afford the gas.