mehoffz24

i put this post here because when i put it in the tech dept they didnt help me so i wanted to talk to you. i have a 95 ta with a lot of bolt ons. rr' s ,pulleys, hpp . ect you get what i mean all the small stuff. when i put the rr's on i adj the valves to 0 lash. i did not like the way the car ran so i loosened them all back up and adj them with car running. this worked out very well had them clacking tightened them till stopped makin noise then another 1/2 turn. i did them all like this. now i talked to a local engine builder in the area and he said to adj them with the car on also. this worked fine for about one month. later on i noticed i was floating the valves at about 5200 rpm, i backed off all the rockers 1/4 of a turn. put it back together all was good for about 2 months. i reinspected for cracked springs but couldnt find anything wrong. it has just happened again and im not sure what to do. the only time it is happening is when the engine is not really under a load. if i smoke the tires in first it will do it but when im ready to shift into 2nd and 3rd every thing is fine. the engine has 92000 in it but still it is intermissant and im not sure what to do.
if i backed them off again just a little more the car will opperate fine but i do not want to go to much because wont i be loosing lift that i gained by putting them on.


thanks in advance

jack stern

LJ93Z28GM

It could be a few poor lifters. Are you getting the noise from all of them?

I typically bring every cylinder to top dead and then tighten the accordingly to the drivers preference.

RunRiot

First, rockers are supposed to make noise, my valve train is noisy as hell and it's running great.

With hydraulic lifters, you never get the full lift until the lifters pump up (high RPM). This is where you're floating the valves, so obviously they're too tight.

BTW I do it with the engine off, one at a time. I use zero lash + 1/16 turn, but I'm using Comp R lifters. I would use zero lash + 1/4 turn with stock lifters.

Alvin@pcmforless.com

Check this out,

I picked this up from my shop foreman as he was adjusting a LT4 vette. Now think about, he is expected to adjust those valves and have them stay adjusted for thousands and thousands of miles. I have gone over a year with this method and no back out on a 127,000 mile car

DO NOT LOCK THE VALVES WITH A ALLEN WRENCH!

With the motor running back the nut off until the rocker taps then tighten until the rocker stops tapping plus an additional 1/4 turn.

At this point take your allen wrench and run the set screw all the way down.

Finally grap your 5/8's wrench and turn the nut anthor 1/4 turn. You will not need your allen wrench for this step. It will be hard as hell but the valves will never back out again.

I always go over the entire motor like 3 times before I totally start locking them down.

Try it, see if it works for you. It sure did offer a much better results than the traditional method for me.

mehoffz24

1st
some of you may have mis underdstood me. im not worried about the noise that rockers make but im conerned with floating the valves at a specific rpm.
2nd
im using the stock studs and i dont have the allen head to lock the nut into place although i know what your talkin about.

3rd
dont you guys find it weird that if they were too tight or too loose the problem would be constant, it only happens when i MAT it in the rain or if im smokin the tires and the engine revs up faster then it would when your runnin some one on the highway.

4th is it bad to use the stock springs with the 1.6 rockers. what are you running.

5th im gonna attempt this one more time and tightin 1/8 turn from 0 lash.

LJ93Z28GM

So you are getting valve float pretty much due to high rpms.

Are your springs getting tired, 92,000 miles is a bunch? Are they the correct spring rate for cam in engine, you stated bolt ons but have you changed the cam? Does there rockers arms use poly locks or just a nut?

It still can be due to poor lifters. Might also want to consider a hydra rev kit. What rpm are you winding it up to?

On a stock motor there is not much past the stock shift point in gains.

AdioSS

you need new valve springs

call summit and get some Crane 10308s for about a hundred fifty bucks

mehoffz24

all of the rotating assemble (internal) is stock, but the rockers. i was thinkin that i need new springs also, never really thought about the lifters being bad, i shift the car at 5500 but raised the rev limited to 6200 or 6300 whatever the hpp is, so long ago i forget. once it goes over 5500 or so it falls on its face. im confused becaue it only does it when the engine is not really under a strain. REMEMBER if i run out 2nd it will not do it. if i run out 1st while spiinin the tires it will do it. WEIRD. and some times i doesnt do it in 1st.

i have poly locks on the studs so why would they back off\

anaik

I don't think poly locks and roller rockers is a good idea. I have stock studs and use the allen head screw with no problems on my RR's.

OneFlyn95z28

I would install new valve springs. I have had the best luck with K-motion k-800s

My Cranes would start giving up after about a year and pick up the exact miss you are talking about