KGSloan

i just got done intalling my heads about a week ago. the heads have valves that are +.070" tallness on them and i'm running stock lifters. jay (absolute speed) said that i would probably need to shim my rockers to get the preload right.

at first, i didn't have the shims. i got 2 full turns of preload and the valvetrain was quiet. then, the shims came in. put in the .060" shims and preload is now 3/4 of a turn and the valvetrain is noisy.


is 3/4 of a turn enough preload for a stock lifter? is it better to have less preload if you're turning high rpms? i am going to be spinning to 7k. what can happen if you run too little preload?

is there anything else i'm missing here? i don't mind a noisy valvetrain, i just want to be sure everything is done right.

KGSloan

anyone???

someone has to know how much preload the stock lifters like?

steve-d

iTrader: (7)

It should be good. Anything less than a full turn is fine. Anything in terms of 1/4 to 1/2 turn is good.

To get a warm and fuzzy feeling that this is good info check this out:

http://www.ls1howto.com/index.php?article=21

Its a "how to" on installing the YT rockers. The info is good and will apply to your install work.

Best Regards
Steve

Country Boy

iTrader: (24)

If your planning on 7k them I would ditch the stock lifters. They usually dont keep up in the high RPMs.

KGSloan

thanks for you input guys, i feel better about where the preload is at.

anybody else?