imo the best way to adjust rr:
set the rr with the motor off 1/4 turn past zero lash, use shoebox's guide. then start the motor and readjust the RR, loosen them one at a time until you here clacking, use your fingers to retighten until it stops clacking (thats zero lash) then add 1/8 turn, then lock your nut down. worked perfect for me.....

Jesse

 

QCKZ28,

How much oil gets squirted around when you do it that way? That's the way I was planning on doing it, but don't want to make a big mess.

Dan

 

id like to know that as well.

 

Its not much. I've heard where people had used half a junk valve cover to block the part they weren't working on. I would imagine just a piece of card board might work too. As long as the engine isn't reved the oil mainly stays put.

Aaron

 

Hardly any oil squirts out. 3 or 4 drops. And if so, big frickin' deal, wipe it off.

I adjusted mine first with the car off, trying to follow the pushrod methods. They were way too tight, it idled really bad like a cam. Thought it was OK. Drove it some, realised it was wrong.

Then I adjusted it again, with the engine running this time. Only way to do it IMO. Tightened them all just enough to quiet them, then adjusted each one (tough to adjust one by ear if they all clack and make noise). Loosen it until it clacks, then tighten it till it doesn't, then 1/4 to 1/2 turn more.

 

some oil will come out, but not alot. i layed a soaking wet t shirt on the headers, to keep the oil from smoking/burning, just be sure to rewet the rags often, if they get dry you will have a fire!!!!
it doesnt take long at all to adjust them with the motor running, 5-10 minutes for each side, be very careful not to drop anything in the motor


jesse

 

yep i adjusted mine by the zero lash method then started the car to make sure everything was fine. at idle i didnt have any oil leave the rockers at all

 

These LT1's are the biggest pain in the A** , when it come to getting the valve lash set right. I set my valve lash so many times, I can pul the valve covers with my eyes closed. Finally got mine right. Had to do it with engine idling. Loosened Rocker until it started ticking, then began to tighten very carefuly listening for the engine to shudder. This is the point that the rockers are too tight, then I backed off 1/2 turn. I could always spin the push rods even when they were too tight. I had them set by getting the push rods to stop spinning, and I cupped all my Roller lifter rod cups so bad that the lifter turned into solid rollers. You may need to check for that. Its easy to push on the push rod and feel that you have spring and approximately 3/16" of travel. If you have no spring left, you need to replace your Lifters and probably your rods too. Another thing, My LT1 cals for 1.5 intake and 1.6 ratio exhaust. Not sure what will happen if you put 1.6 on intake. The intake valves have more room to play than the Exhaust valves do, so collision between the valve and piston is common also with the exhaust valve. Basicaly in closing, the only way I could be sure that my valve lash setting was not too tight, was to take them to too tight then back off. You get a noticable shudder when you leave the valve open on a cylinder.