Jrp1978

iTrader: (10)

I was playn around today and left astop light revved it pretty good and when it idled down had a top end tapping sound .........well i freaked out pulled over and went to check it out when all the sudden it just went away and it purs like a kitten ? No power loss ! oil pressure never didnt anything different still hits 65 when u rev it up .

What the hell was it?

KrisXpc

iTrader: (13)

Rockers chatter sometimes. Might have not been anything really..

Jrp1978

iTrader: (10)

I Mean It Was Loud And 2 Blocks Later Went Away ?

Zitty'sZ

iTrader: (29)

My car does this too , but after idleing a few minutes it quiets down. I 'm running Harland Sharpe rockers and they seem to be a little more noisier than the stock rockers anyhow .

Jrp1978

iTrader: (10)

i mean if i spun it it would be shot right

cherryelky305

iTrader: (2)

i would think a bearing would be knocking all the time and go up with rev's. these engines are just noisy sometimes.

TopFlite

A lifter may have been slightly stuck momentarily. What kind of oil are you using?

Soul TKR

iTrader: (4)

a bearing would give you a "clanking" noise and increase as you hit the throttle... If it's not doing it anymore your probably fine... otherwise something could be going on in your valvetrain...

Jrp1978

iTrader: (10)

its 20 50 mobile one i am running that because tsp told me it would help with vavle train noise

Captain~Morgan

Sounds like a lifter to me. You may have one bleeding off a little at high RPM which would explain the temporary ticking noise that went away once the engine was idled down and had a chance to build pressure back up in the lifter. Try revving the motor up again similar to how you did before and see if it does it again.

outkast6991

iTrader: (34)

20w50 is way thick

Thorny

iTrader: (14)

I just recently learned that a spun bearing doesn't always make noise all the time. I just pulled my motor last month for a refresh because it made an intermittant knock at higher rpms under load, turns out it had spun a bearing. It made NO noise at all under 3500 RPM and had great oil pressure. I never would have heard it until it was too late had I not had it on the dyno where we could hear it under the hood while it was under load. Turns out it had spun the #1 rod and the #2 main was torn up pretty bad but stayed in place.

Jrp1978

iTrader: (10)

It did i again tonight . revved it up took off came to a stop clanking . let it set running 3 minutes went away . still a very very faint sound but nothing like before

TopFlite

Yea, 20w-50 is on the heavy side for LS1's and their direct engine block descendants. Stick with 10w-40, 10w-30, or 5w-30 if you'd like.

Soul TKR

iTrader: (4)

makes me think it'll progressivly get worse

mine did about 10 runs on the dyno with a spun bearing till we finally decided to give it a rest before a piston shot out the side of the block

mine had some clanking going on... pulled apart the valvetrain, found 3 bent pushrods... dug deeper and found a failed lifter... dug even deeper and found the spun bearing and rod knock...

bad news = engine was gonna need some work
good news = got a new, built engine

chub406

its the 20-50. its too thick to keep the lifter pumped up. the hardcore factory guys run 5-30. change it over to 10-30. then see what it does. its cheap and easy to diagnose.