Ls9 Dohc???...
#1
#3
Re: Ls9 Dohc???...
Like I said over at digital corvettes, I don't know why they would go DOHC again. I really do not see the need for it, but I am sure Chevrolet put a ton of thought into it if that's what is coming................. and yes the document does appear to imply a supercharger (look under "Deliverable(s) towards the bottom of the page).
David
David
#5
Re: Ls9 Dohc???...
I don't see the need for it either, they are doing just fine with their pushrod engines. I was never a big fan of the DOHC 3.4L that GM use to have, I doubt I would be a big fan of the Ls9 either.
#6
Re: Ls9 Dohc???...
I also agree that there really isn't any need for it...But, if they really intend to put this into a "Super" 'Vette than maybe it's a decision that's been made from more of a marketing standpoint vs a performance standpoint, (though in theory a dohc s/c'd motor should outperform a pushrod version especially with respect to top end, gas mileage and smooth operation). Public perception still seems to be that pushrods are old tech and are outdated and while we all know that this is BS, GM could be making their top of the line motor dohc just to give it a more exotic appeal
#9
Re: Ls9 Dohc???...
Originally Posted by Z28x
Maybe it is the new Northstar for Cadillac V-series cars.
Very interesting, though I doubt a Corvette will have anything but OHV for quite a while.
#10
Re: Ls9 Dohc???...
Either its BS, which I suspect, or the code V8GDOHC DOESNT mean V8 Gas Dual Over-Head Cam, but rather V8 Gas Direct Over Head Cam (as we know GM is moving toward Direct Injection engines).
Who knows, but I dont see GM going DOHC. No need, and the LS7 already pushes silly high revs. RPM is what kills an engine, and we need to keep our engines low in revs and high in grunt. Thats what makes them last, and makes them reliable, which makes customers happy.
Also DOHC is more expensive, a larger engine size, heavier, and more likely to break.
Who knows, but I dont see GM going DOHC. No need, and the LS7 already pushes silly high revs. RPM is what kills an engine, and we need to keep our engines low in revs and high in grunt. Thats what makes them last, and makes them reliable, which makes customers happy.
Also DOHC is more expensive, a larger engine size, heavier, and more likely to break.
#11
Re: Ls9 Dohc???...
Originally Posted by Geoff Chadwick
Either its BS, which I suspect, or the code V8GDOHC DOESNT mean V8 Gas Dual Over-Head Cam, but rather V8 Gas Direct Over Head Cam (as we know GM is moving toward Direct Injection engines).
Originally Posted by Geoff Chadwick
Who knows, but I dont see GM going DOHC. No need, and the LS7 already pushes silly high revs. RPM is what kills an engine, and we need to keep our engines low in revs and high in grunt. Thats what makes them last, and makes them reliable, which makes customers happy.
- The primary benefit of OHC is not to simply to rev high.
- High RPM does not kill an engine; that's an old wives' tale that might have been applicable 30 years ago but certainly isn't today.
As 91_z28_4me noted, it's most likely the next generation of premium V8. It's been rumoured for some time that the next "NorthStar" would be based on the LSx. There would still be an OHV variant for the masses though.
#12
Re: Ls9 Dohc???...
Originally Posted by R377
As 91_z28_4me noted, it's most likely the next generation of premium V8. It's been rumoured for some time that the next "NorthStar" would be based on the LSx. There would still be an OHV variant for the masses though.
Don't the N* and LS motors already share firing order?
#13
Re: Ls9 Dohc???...
Most likely a Cadillac application, but i could see this in a premium chevy like the corvette. Maybe it'll be a replacement for the Ls2 in the base corvette and CTS-V which'll allow the corvette/CTS-V to have a different engine than the other mainstream GM performance vehicles like the camaro, GTO, SSR, TBSS, etc.... I could see GM going this route. A supercharged version could also see special use in the cadillac STS-V, XLR-V, and maybe Z06. I wouldn't mind the z06 moving up to a S/c'd Ls9 Dohc and it leaving the Ls7 for cars like the camaro/GTO.
GM does need a high output Dohc v8 for their premium cars. Not so much for performance, but for image, etc... In this day and age when companies are toting things like Double Vanos, Individual Throttle Bodies, direct injection, vartiable turbine turbochargers, 5valves/cyl, etc.... the public looks at GM's rather simple pushrod v8 motors as lacking (even though we know for a fact that isn't the case). In this industry, image is almost more important than the practicality of the application because people just love having things for the sake of having things. It's dumb, but that's the masses for you.
GM does need a high output Dohc v8 for their premium cars. Not so much for performance, but for image, etc... In this day and age when companies are toting things like Double Vanos, Individual Throttle Bodies, direct injection, vartiable turbine turbochargers, 5valves/cyl, etc.... the public looks at GM's rather simple pushrod v8 motors as lacking (even though we know for a fact that isn't the case). In this industry, image is almost more important than the practicality of the application because people just love having things for the sake of having things. It's dumb, but that's the masses for you.
#15
Re: Ls9 Dohc???...
Originally Posted by 91_z28_4me
Don't the N* and LS motors already share firing order?