I just bought an 01 Z28 with 64k on the odometer and have the after purchase worries....

Describing engine sounds is pretty hard but this is what I'm hearing from this aluminum engine as opposed to my LT1s. I've placed a stethescope on the valve covers, intake, heads, block and oil pan but can't detect what I hear and feel while driving.

Cold start, the engine has 'almost' a diesel rattle; its not loud or pronounced but to my ears, it's there. When warmed the engine sounds okay until 2k rpm where there's a performance sounding intake rap. Hot, the engine sounds rather normal at all rpm but there's a light pulse during acceleration that can be felt and heard. All hp engines that I've encountered have this once per rpm variance in the exhaust note, otherwise they would sound like sewing machines but with this engine I can actually feel it in the shifter and steering wheel. It's slight but another non camaro driver noticed it too.

The intake rap I mentioned at 2k rpm is reminiscent of a 92 3.8L ford engine I once owned. The crank beaings were shot. I'm having a hard time believing the bearings are gone on this engine because hot idle oil pressure reads 45 - 50 psi according to the gauge. Besides that, the ford's engine noise worsened at high engine temperature. This LS1 gets quieter. I've gone to redline a couple times and all seemed well.

I'm worried that the dealership may have been running 87 octane because when they went to fill the tank after the sale, I reminded the salesman it needed 92 octane. He was surprised....

I know what my LT1s with automatic transmissions sound like but this LS1 with the M6 is a different animal.

Can someone who has owned this engine for a while tell me what I should be hearing from it? Thanks....

http://tinypic.com/ele42x.jpg

 

Ls1's do seem to be noisy until there warm up...Your case is probably Valve tap,it is a normal LS1 symptom...according to GM its harmless and normal.

 

Aluminum engines are always more noisey than cast iron.

 

Thanks guys. I can get some sleep now.

 

BTW, the LS1 can run 87 octane.

 

Thanks for that information. I have been so busy reading the owner's manual to un-LOC-k and remove the SEC setting for the radio and figure out why the horn blows when locking the car up that I haven't taken the time to read things like that.

Now to tackle the skip shift problem....

Regards

 

I've been running 87 since the gas prices here have gone past $3/gal. Just the knock sensor goes off alittle more than usual.

 

I'm surprised no one has mentioned the piston slap to him.

GM overbored the #8 cylinder on 01-02 cars, and the sound at cold-start can vary from nothing to downright annoying. It will go away or get quieter as the engine warms up, and supposedly doesn't affect the performance or life of the engine.

There is a proposed class-action lawsuit at this time pending against GM from the vehicle owners. A search should net you some more specific information.