WhiteDiamond

I am looking for some "educated" guesses on the new cam specs GM is using in the LS2 Corvette motor. In the press introduction, GM stated the lift of the LS2 cam is 13% more than the LS1 cam currently used in the Vette. I believe this puts the lift somewhere around .540 on intake and .530 on exhaust. Considering the valvetrain noise issue GM complained was the reason behind the LS6 cam in 2001 being smaller than 2002 up, what do you think GM did to the duration of the LS2 cam to get these lift numbers? I believe the current LS6 cam specs are .551/.547; 204/218 on 117.5 lobe seperation.

Todd

LS1derfull

Since valvetrain noise is caused by ramp speed and lobe intensity, its a safe bet GM added some duration to both lobes and spread the LSA to a spec similar to 02 LS6.This allows greater lift with similar lobe design and no extra "noise"

WhiteDiamond

I have another curious question about valvetrain noise. If you reduced the weight of the valve, therfore allowing a reduction in the spring rate, can you have a faster ramp rate with similar noise to a typical "heavier" valve and higher spring rate?

Todd

Scott Turvey

Assuming the noise was coming strictly from the valve face striking the valve seat, theoretically yes. However, increasing the ramp rate might be re-introducing the problem. Either change is going to shift the harmonics, so practically speaking, it would be a try and see proposition in my opinion.

LS1derfull

I look to what GM engineers did with 02 LS6 valves and the weight reduction/spring tension plan they used there. This was in the name less wear and noise with safe valve control to 6500 that the motor is allowed to turn stock.Corvettes engine covers are there to dampen noise also.