2000 corvette ls1 noise

[foruwhatisit]

My ls1 motor has a taping or knocking noise ( generally cold start, but not always) that starts about 15-30 seconds after start uo and with in about 1 min. or so it will just fades away. If car is put in gear the noise will generally get a little more louder. I am 100 % sure its not comming from the crank assy. TO ME it seems like a lifter loosing prime then pumping back up as it starts as a tick that becomes more of a knock then returns to a tick then goes away!??
Do these motors have any problems with lifter failure, rockers backing off, push rods bending, or upper end oiling ?

[Spaz]

sounds like oils isn't geting in to the heads and the valves are making some chatter...

[foruwhatisit]

i thought that the lifters on the LS1 motor set in a dished out resivore that worked as a oil bath or can this have to do with an oil O ring Ive been reading about on the oil pump that lets the pump pull air into the oil. On that thought I might do a cold start up and see if the dipstick oil looks foamie??? Im evaluating every opinion with in reason. any ideas would be of help. THANKS

[qwk93ta]

Could this be piston slap that many LS1s have?

[gnomee]

Sounds like its the standard piston slap. Some cars have it some don't. They have since modified the piston and I think have this issue solved.

Either way GM says its just some noise and not a big deal at all.

Don't sweat it just let it warm up.

Welcome to the board!

[1BadRamAir00]

I agree I have had many LS1's and a lot of them have had this problem as well and nothing in the motor has broken on me. And I sprayed 1 of those noisy Ls1's for over 3 years. I sold it now but it still ran no problems other than it smoked when you got on it hard but your talking 3 years of Nitrous every other weekend threw it. So I i think its good. Like stated let it warm up before beating on it.

[foruwhatisit]

Thanks to all that have responded. From all of you and other sources I do think that it is more than likely piston slap.

[locojoe]

I have a 2000 C5 and I get some what sounds to be lifter noise at RPMS over 2000....any tips on where to start ?

[INMY01TA]

Ya sounds like piston slap. Ignore it.