I have read a lot of posts before I set my valves on my cam instal. I only did a little 212/218/510" cam because the oem cam lost a lobe and lifter roller. I set the valves at 5/8 turn each and it fired up quieter than ever. Now, fifty miles later, there is a mild symphony going on under the valve covers. The clatter is just a little bit louder than the original stock valvetrain was, so I'm not afraid of it. Within this forum, most seem to suggest 1/2 turn. Outside of the forum, I have asked a lot of pros and quite a few suggest the full one turn past zerro lash. Because I have a new cam, stock type new lifters,and new 1.6:1 stamped rockers, I figure some of my adjustment was lost with new part wear in. Soon I will remove the valve covers and turn each an additional 3/8 turn to catch up to a stock setting. I would like to hear from you guys out there who have set their valves at 3/4 to 1 turn past zerro, and whether you have a stock sounding valvetrain, or still have some clatter. I am aware that my comp#501 has steeper ramps,and that my Isky springs are a lot stiffer than stockers, so should I expect more valvetrain noise?
thanks , Edman

 

If you're going to set your valves to 1 turn, you may want to start anew with the adjustment process. In other words pull the lash out to zero and then go your 1 turn. Totally readjust them. Probably be way more accurate that way.

When my Z was stock, I had some valvetrain clatter, reset the lash to 1 turn. It was gone for about 10miles then came back. I put in some 1.6:1 self aligning roller rockers, did 1 turn valve lash and still had the symphony. After thle latest round of mods, heads, cam, LT's, I set the lash to 1/2 turn as suggested. Car runs great and the symphony sounds great too. From experience, I think these LT1's have a bit of inherant valve traio noise that you cant get rid of.


Also - are you interested in a set of COMP Magnum 1.6:1 non self aligning roller rockers. You'll need guideplates and hardened pushrods but they're pretty cheap. PM me if your interested. I have a new set, unused in the box, that will fit the LT1, for $70. Was going to used them on my latest setup but went with ths COMP promags instead.

 

As far as I'm concerned the most foolproof way to adjust the valve lash is with the engine running. Just slowly loosen each one until you start to hear it clatter, then tighten it back down until it's quiet, plus 1/4, 1/2 or whatever amount of turns you feel comfortable with. I personally set them at 1/4 turn and have never had a problem.