I Just did a compression test on my 01 cobra that i bought a week ago, well me and my buddy did i sat in the drivers seat and cranked while he watched the compression guage. We disconnected all the spark plugs and held the throttle wide open (the motor was slightly warm had been sitting about 2 hours after being fully warmed up when we did the test) and according to my friend each cylinder read 175 psi i would think it would vary a little but every cylinder said 175 psi. Whats your guys thoughts on this? what are the compression numbers supposed to be. The car has 39000 miles.

 

If all of your cylinders read 175, then you are good!

 

Consistency in the readings is what you're looking for, so if all are reading close (within a few percent), then you're good.