i have a stock gsr buttom end with stage 3 cams now i used my friends compression test and he said he has used it on the car before i got it and got 160 psi in each cylinder i was expecting alot more is his compression tester broke

 

those number look about right.

 

Bigger cams bleed off more compression than stock cams. As long as the numbers are close (within 20 lbs of each other), you should be ok. Normal reading for a stock gsr should be close to or more than 200. But as i said the biggers cams will make it read less also.

 

yeah it read 175 all the way across