zr1intrning

hey, i've got a 2002 zo6 with a stock ls6 in it.
i've come across new rocker arms for it with ratios as high as 1.85:1. just wondering how big can i go with the ratio on a stock cam before the vavles start making contact with cylinders. chances are i will just stay with the stock cam forever.

any comments or concerns would be greatly apreaciated
thanks
-dave

vettenuts

iTrader: (4)

Likely any of them as the duration is the issue and the stock cam duration is pretty low. However, you will definitely need better valve springs to keep control of the valve train.

1SLwLS1

iTrader: (6)

yup, duration is the killer, not the lift. Your stock springs will probably bind, you'll need to upgrade.

Hamrdown

iTrader: (25)

By the time you get a good set of high lift rocker arms and replace the valve springs it's pretty close to the price of doing a cam swap. And you will definately gain more from a new cam. Just my .02

02*C5

iTrader: (1)

The LS1/LS6 valve train is made to run with the 1.7 or at highest 1.72 rockers. I have seen a lot of the LS1/6 run into valve train failure because these heads and most of the shelf cams that you will finds run w/ the 1.7 rocker ration.

The only thing you are gaining is lift and doing so in a very unsafe manner. If you want more lift get the cam that has the lift you want.

You need to get a cam that 1 works with the 1.8 rocker ration safely. 2. you need to upgrade your springs, rods, heads and everything that will work with that rocker ratio and like stated above once you have safely worked your whole valve train to work on a 1.8 rocker ratio the money spent would have been better spent on a cam that would gain you HP.

Rockers DO NOT make any DIFFERENCE in hp Gains. at best you are looking @ 1 to 2 hp gains that are with in the margin of error of any dyno and not noticeable.

Bets advice get the trunnion upgrade for the stock rockers. That way you can go beyond a .650 lift and do what ever cam makes your heart flutter. with the LS6 you can see cam sizes in the 24X/24X easily with no issues and a higher duration with no ptv issues than in an LS1.

Good luck.

evangto87

iTrader: (6)

Im not so sure I agree with this statement.... there have been many a case where people have made more power on the dyno as well as ran better times at the track with 1.8 rockers.

zr1intrning

just want to thank everyone for the advice.
so pretty much from what i get is for the minimal gain in hp the money could be much better spent else where.

evangto87

iTrader: (6)

It all depends what your trying to do... it usually is cheaper to get a cam with the correct amount of lift your looking for. I however am doing the ls6 cam with 1.85 rockers. I have a different goal in mind then some people and in some ways it will cost me more money. But there are various threads showing you will pick up some hp with rockers. However rockers on an ls1 cam would be a waste completely. I'm building a bastard GM motor. Pure sleeper build. If your gonna go the rocker route.... get an ls6 cam. If not. Just buy a cam that doesnt need rockers.