Hey guys, I've got a LT1 swapped into an '89 that I run pretty hard. We've always been a little unsure about how to tighten down the rocker arms, as once we over-tightened them and were utterly bewildered by our lack of any compression whatsoever. What I've heard is tighten until you can't spin the pushrod, then go 1/2-3/4 of a turn more. The problem is we do that, crank the engine around by hand, and the pushrods are loose and spinning around again. (Re-tightening them lead to the no-compression scenario) This leads to a really noisy valvetrain and I'm wondering: These are hydraulically adjusting lifters right? If they're worn out, they wouldn't adjust properly anymore, right? We could swap the lifters relatively easily, but would that fix it? What else could cause upper-end rattle? Any ideas are greatly appreciated!

 

On any LT1 I have worked on I always adjust the rockers with the engine running and go through them one at a time. I loosen it until you can hear some noise and then slowly tighten it until the noise goes away. I have always had good luck going a 1/2 turn further. Now on a friends LT1 with Jesels this will not work, but for a roller rocker or even a stocker it will work for you. Be careful when doing it like this though as oil can get on the manifolds if you are not careful. I made a cardboard template to stop this from happening.

 

Yeah this is all stock, in fact I'd wager it's the factory lifters, which are at probably 120k and ~23 hours of racing now. These cardboard templates, they just fit into the valve area to keep the oil from splashing out? Do you have a picture? I like the idea of doing it that way.