L99 + VVT mods

[toehead93]

Ok, I'm glad to see so many mods this quickly for the Camaro and there are many more still to come. What I haven't seen are any specific to the L99 that take advantage of the Variable Valve Timing. What kind of gains can we expect to see with tuning the VVT, are any shops testing new camshafts that utilize VVT and what kind of gains are they getting? I know some work has been done for the G8 but the G8 is not an L99.

Same goes for transmission tuning, although I'm a little reluctant to tune the transmission for the sake of the warranty.

[RonC]

The G8 doesn't have VVT, but does have AFM. They have done some work on the G8 with a cam change still using AFM for about 45 HP gain on the 6L. Comp Cams has VVT cam upgrades now for up to 70 HP gains. You might check out their website for details. They will surely come out with VVT and AFM compatible cams soon. Looks very promising.

[MadMaxx]

Ummm... the VVT system in the L99 is more of a mechanical phase shifting of a single cam (intake/exhaust, as it's once piece) than the way most think of VVT (OHC) setups.

http://gmhightechperformance.automot...ve-timing.html

[Gentry78]

i would say check out some some challenger,charger,300 forums the new 5.7 hemi has mds and vvt. see what they are doing

[SubSolar]

Originally Posted by MadMaxx

Ummm... the VVT system in the L99 is more of a mechanical phase shifting of a single cam (intake/exhaust, as it's once piece) than the way most think of VVT (OHC) setups.

http://gmhightechperformance.automot...ve-timing.html

Damn, so tuners won't be able to change valve timing on the fly, kind of like an imaginary variable camshaft?

[pharmd]

These guys have been doing VVT "performance" longer than anyone...

Mast Motorsports Track Package

It will be able to be tuned. Basically, unlike the LS3 that when you run a larger duration cam you start to sacrifice low end torque to attempt to gain high rpm horsepower, and you begin having piston to valve clearance issues as well. With the VVT technology, you will be able to run a longer duration cam, gain top end HP, retain/gain low end TQ and avoid PTV clearance issues. These cars are heavy, losing low end torque is not an ideal situation for performance. Yes, there are ways around it, but all things being equal, if you make equal hp on top, but more low end (then combine that with a stall and MT DR's to 60' well) then you should have a very nice combination for drag, or road course (you'll need tq to power that heavy beast out of a turn, or to accelerate away from a low speed apex).

[SubSolar]

Originally Posted by pharmd

These guys have been doing VVT "performance" longer than anyone...

Mast Motorsports Track Package

It will be able to be tuned. Basically, unlike the LS3 that when you run a larger duration cam you start to sacrifice low end torque to attempt to gain high rpm horsepower, and you begin having piston to valve clearance issues as well. With the VVT technology, you will be able to run a longer duration cam, gain top end HP, retain/gain low end TQ and avoid PTV clearance issues. These cars are heavy, losing low end torque is not an ideal situation for performance. Yes, there are ways around it, but all things being equal, if you make equal hp on top, but more low end (then combine that with a stall and MT DR's to 60' well) then you should have a very nice combination for drag, or road course (you'll need tq to power that heavy beast out of a turn, or to accelerate away from a low speed apex).

Cool. What about non cammed cars, will they be able to provide a good performance tune with VVT with basically stock cars (maybe intake/exhaust)?

[pharmd]

I'll be able to tell you more after I get my car and my tuner and I start working on it. I have both HP tuners and EFI live, but I haven't had time to look at it and see what they have for this ECM. As you can see in this pic, in the upper right hand corner, the tuning options are available in the latest Beta edition of HPTuners...Now, its up to you to find a reputable shop that has experience working with this technology...I would probably be a little hesistant about letting just any backyard tuner start screwing with my VVT settings.

[kdoske]

Originally Posted by SubSolar

Cool. What about non cammed cars, will they be able to provide a good performance tune with VVT with basically stock cars (maybe intake/exhaust)?

umm no, non cammed cars don't move at all--cams required. I think a good tune will give 30-40 HP.

[SubSolar]

Originally Posted by kdoske

umm no, non cammed cars don't move at all--cams required. I think a good tune will give 30-40 HP.

"Cammed" means there's an aftermarket cam, silly. Just like people don't say they "have an aftermarket exhaust", they say they "have an exhaust." Obviously all cars have some sort of exhaust, haha.