Hi, guys. I've had my 1999 30th Anniversary T/A for about six months now and just got around to doing a compression test on it. The car runs strong and smooth, uses no oil, makes no noises and has good oil pressure. It is pretty much stock and has 88,000 miles on it. I got 145 as my low cylinder and 165 as my high cylinder. The numbers did not seem be favor either bank or paired cylinders. I "wet tested" my two lowest cylinders, which came up about 15 to 20 psi. I also put air pressure in my lowest two cylinders to see if I could hear any unusually heavy pressure leaks, which I didn't.

I've worked on cars for many years, and, normally, I would call this a "good" compression test, since all cylinders were pretty close on compression. But I've heard from LS1 people that compression typically runs about 180 to 200. I even bought a new Snap-On gauge and checked my lowest cylinder again, which came up 145 again.

What do you guys think?

 

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My LS6 had 210-220 psi per cylinder. Are you keeping the TB blade open while cranking?

 

that sounds about right, the 98-00 have a little more cam duration that might be bleed in off some pressure compared to the ZO6 numbers above

 

Yes, my throttle was blocked open during testing. Also, the engine was warm.

 

Whats the milage?

 

Hey jub jub does that 226/230 pass Ca. smog?

 

No way!

 

The car has 88,000 miles on it.

 

What do you do about smog in Ca.????

 

Cheat and add a little methanol to the gas.

Jason