Ponyhntr

iTrader: (9)

I have been fighting a valvetrain noise on a 02 TA that has a 402 with ported 6.0 heads, stock rockers, and Comp "R" lifters.

I just measured the preload and I got .020 with a 7.400 pushrod.

I think I remember reading that the 'R' lifters don't want much preload at all, but is this too little? If so, what pushrod would you recommend?

Thanks for your help!

ls2 bait

iTrader: (11)

that sounds like way too little. id do .050. do a 7.425 pr and itll give u .045 which should be fine if they dont like alot of preload.

hvyhttter

iTrader: (3)

OOHH no .002 basically zero lash

Ponyhntr

iTrader: (9)

That's what I was thinking...

WS6nJAX

iTrader: (207)

i believe the recomended preoad is .002-.004 on a warm engine and adjustable rockers are suggested also. i used them once before and i set them at .010 on a cold motor with adjustable h.s. rockers.

bayer-z28

iTrader: (14)

X2..

Something about the .020 threw a flag in my head. Try .050 Pre-load and see where it takes you.. ADJ rocker may be soon in your future.. easier on the wallet in the long run.. Just a couple of minute adjustments instead of waiting for new PR's.

vettenuts

iTrader: (4)

0.050 is 0.048 more than Comp recommends. These are impossible to set up according to Comps requirements without adjustable rockers.

hvyhttter

iTrader: (3)

Definately agree, say high to hung open valves on COMP "R'"s

JPH

iTrader: (2)

Who sold you those Comp R's? I never use those lifters. Do like we talked and if the noise goes away, you know what to do then.

brad8266

iTrader: (23)

R's are supposed be like .002-.004 preload, basically no preload whatsoever.

ls2 bait

iTrader: (11)

that just sounds like a recipe for disaster imo. i would never use a lifter that only recommended that. i wouldnt feel safe.

Ponyhntr

iTrader: (9)

OK, after talking to my source at Comp, he said that the optimum preload on 'R' series lifters was .004-.010" of preload. Since there was basically no way to get there without adjustable rockers, I decided to put a set of LS7's in the motor. Guess what? The noise is still there!

I didn't get a chance to check the preload, but the only thing I changed was the lifters.

Could this be a oil pump problem after all? The noise is not there at idle. It only becomes apparent after cruising down the road a mile or two. It is definitely RPM-related, and after sitting and idleing for a minute or so the noise will go back away until driven again.

It's got a stock 2002 LS1 oil pump in it. With fresh 5/30 mobil 1 it has about 45 psi of pressure on the gauge when hot. The oil level while ticking is full.

I can't figure this damn thing out!

Thanks in advance for any advice!

Unaffliated Racing

iTrader: (15)

I guess you will never run a solid roller then. If .002"-.004" preload bothers you .028" lash will scare the hell out of ya

vettenuts

iTrader: (4)

How did you install them. Did you measure with an adjustable, if not you need to do this to ensure the correct preload. Too little preload will be noisier. If you want to verify the preload, measure for the required length.

ls2 bait

iTrader: (11)

no i havent. im a newbie

JPH

iTrader: (2)

if its an A4 car josh, recheck your convertor bolts.

Ponyhntr

iTrader: (9)

Here's an update for you guys...

I finally got a chance to check the preload with the LS7 lifters and the 7.400 pushrods. I now have right at .050" preload, which is about right, correct?

I'm starting to REALLY DISLIKE this car!

Ponyhntr

iTrader: (9)

Joe, it's a 6-speed car.

vettenuts

iTrader: (4)

You want 0.080" - 0.100" if you want it quieter. Sounds like 7.450" would do it.