edwardzracing

iTrader: (59)

I'm hunting for people that have these 1.85 rocker arms on their cars and are running them without any noise in the valvetrain. I'm having a horrific time getting them to shut up. The heads are more than capable of working with them, I just can't get them adjusted right. Is there a certain process I should be taking? I've tried Comp's method, but hell it doesn't seem to be working... tried the Crane method of waiting 15 minutes and making a quarter turn, but that doesn't seem to have worked.

Anyways, I'm hoping, and I'm sure there are many, that someone on here that has them working correctly and silently (or close to it) will chime in and be able to give me a little insight on solving this issue. I've checked everything else... valve springs are perfect, lifters are brand new as well and seem to be just fine. Tuner was able to tune the car, but at WOT, the valvetrain is making enough noise to throw false knock at the sensors and it's pulling timing. I'm running a pretty light oil too... 5W 20... plan on changing that after I adjust the rockers again, but lightweight oil shouldn't be causing it to clatter that much should it?? Either way, I'm going back to some regular weight stuff. Anyways, I want to run the car at a Test & Tune next week, but am not going until I know the car is running right. So if anybody can help, please do. Thanks for reading, and thanks in advance to anyone who might respond.

Brad

vettenuts

iTrader: (4)

How "exactly" did you adjust them?

edwardzracing

iTrader: (59)

http://www.compcams.com/Technical/In.../Files/151.pdf

See step 7.

That's how I adjusted them. Another note, I'm running the Comp Pro Magnum Lifters as well.

edwardzracing

iTrader: (59)

Bump for help.

vettenuts

iTrader: (4)

They say 1/2 turn. That is 0.032" pre-load by my calculations. I would go 1-1/2 turns which should give you 0.096" lifter pre-load. That is likely why they are so noisy.

eallanboggs

iTrader: (1)

I've installed them using R lifters. I use zero lash. If you use OEMs you need to add some preload. I have no lifter noise(it will sound like a sewing machine when first started, but after that nothing). Do you have sensitive fingertips? Apparently some people have a problem determining when they have reached zero lash. I'm beginning to believe finding zero lash after reading so many posts about this.

edwardzracing

iTrader: (59)

Zero lash is when the pushrod has no vertical play and you can feel tension on the pushrod when trying to turn it with your fingers correct? That's where I now have them set... going to put in slightly thicker oil and run it again... we'll see what happens. Hopefully it's better. Race day tomorrow, and I'd really like to see what this new combination can do. Thanks guys!

vettenuts

iTrader: (4)

Zero lash is when you take the play out of the valve train, best way to check is by gently lifting the rocker nose to see if there is any clearance (don't lift so hard it depresses the lifter cup). Once you have zero lash, you need to go 1-1/2 turns to set the preload (0.096").

chriswtx

iTrader: (5)

I set my Comp 1.75s up at 1 1/4 turn after zero lash . That came out to .080" of lifter preload on my stock LS7 lifters......

gametech

iTrader: (1)

I put some of those in my work truck over 150k miles ago. I keep threatening to re-adjust them , because they are noisy. Maybe one day I will get around to doing it.

chriswtx

iTrader: (5)

Also to add to this, I had to remove the little tin splash shields inside the valve covers. The lock nuts were touching and echoing noise to the outside...

eallanboggs

iTrader: (1)

Zero lash is for Rs. With OEMs you have to add some preload. Use your finger tip in conjunction with your other hand which is turning the wrench. Just remember that lifters that have bled down have a different "feel" than ones that are still pumped up(full of oil). You must be "sensitive" to the difference when trying to find zero lash. This is not an exact science. There is no substitute for experience in this regard. Turn the wrench slowly once you get close to zero lash and continue to spin the pushrod with your finger tip. You're waiting for a change in the resistance in the pushrod and wrench.