Hi havent posted on here for a while but i have a GD cobra with a stock ls1 engine in (for the moment ) the engine has been in for a while now and has been running fine been on the dyno and put out a nice 340 BHP flywheel (360 on race fuel ) but now i can here a very slight knocking noise coming from the engine its hard to pin point where its coming from but it sounds like a bottom end knock, im sure it cant be the noise goes after a slight rev and is fine when driving. oil pressure is 50-60 psi cold 30-40 warm ( i think havnt had it warm in a while) but there does seem to be some valvetrain noise also when reving... but i have herd this is fairly normall.

has anyone else herd of this? should i be worried?

sorry if its abit vage but somone may know what it is!!!

thanks alot

Ricky

 

If it sounds kinda like a sewing machine, that is normal LS1 valvetrain noise. Have you revved it past 7K? That could be a problem with your rod bolts. Lets hope that's not it@!

 

yes almost.. its a rotaional noise that i hadnt noticed before. never been past 7000 well not since i have had the engine anyway !!

thanks