n2o98T.A

i have a knock coming from the pass side of my engine.
no idea what it is exactly but it sounds terrible around 3-4 rpms after that its to loud to hear the knock or it goes away.
i pulled the valve covers on it.all but a couple of my roller rockers have side to side free play in them. can anyone tell me how if i should tighten them or how i could fix this knock?
its a ls1 trans am btw

Abuckeye

Could be the rockers getting ready to go. Whatever it is don't take any chances or you'll be knee deep in a new motor.

95_ls

iTrader: (4)

could also be lifter noise

BlackScreaminMachine

iTrader: (17)

There is no adjustment to stock rockers. Hence why it becomes a PITA that everytime you put a different cam or smaller CC chamber head that you need to measure the PUSH ROD length.

Question is does the noise go away after time or is it always there?

Stock rockers are known to puke out their needle bearings but engine temp should not change that noise, also the bearings would be in the oil pan. Do a search on Trunion Upgrades.

IMO if it does go away, you have piston slap. IF it does not and is always there and the tone/pitch changes as RPM increases, it can be a bearing.

I myself have seen cam lobes get wiped but you would need to pull the heads to inspect so I would eliminate all other possiblities before hand.

99TNA

i too have the same issue with a 00 TA, knock comes and goes with rpm, it is there at idle and cold (loud) then louder if you slowly let out of the clutch,(when cold) on the cylinder 1 sounds like, switched the oil from mobil 1 to Ams oil, hoping it was the notorios piston slap, didnt seem to change it much, (with mobil 1 you could hear it on slow accel. not with the ams oil tho) car has great oil pressure, so i was almost ruling out a lifter

im lost on this one as well ..

95_ls

iTrader: (4)

i dunno how that would rule out a lifter if its collapsed and wont pump up still (assuming u have hydrolic lifters) even with the change in oil i dont see how that would rule it out ??? not tryin to be an *** i just dont follow u man

NC98Z

iTrader: (1)

If you have long tube headers with the EGR pipe on it check for a stress crack where the pipe is welded to the headers. I had this happen on mine and had to get it welded. Raised all kinda hell before it finally broke off.

99TNA

na i under stand its just when a lifter in my 79 went down oil presure droped significantly, so thats the only reason why but it very well could be, are they know for having issues with the lifters?

95_ls

iTrader: (4)

seems to be pretty common, i swaped a mild 224/224 .581 cam in it and didnt replace the lifters and after bout a month i noticed a lot of valve train noise assosiated with a collapses lifter i ges they dont respond well to more lift