I bought an LS1 with T56 (2002 from a Trans-Am, stock internals) off Ebay awhile back. I just got around to doing a compression check today. Here are the results in psi...95, 205, 210, 40 (from front to rear on the driver's side) - 110, 200, 160, 160 (from front to rear on the passenger’s side). I tested it 3 different times and got similar results. What should the psi be per cylinder? I feel like I know the answer to this but what do I do now? Is it rebuild time? I'm planning to install a Procharger (already bought it) so should I take this as an opportunity to put some aftermarket parts in the block? Thanks.

 

Especially from the readings on your driver side I say ya its time for a rebuild. Does the motor have blow by? I believe normal should be between 160-180 PSI if I'm not mistaken. Also since your going with a Procharger I would recommend getting forged internals.

 

Blow by, what's that? (Sorry newbie here) I'm not sure about the running condition of the engine -if that's what you mean.

 

Do a leak down before you make a decision.
Your rings could be fine and you'ra having valve leaks