after searching, i didnt find a dedicated thread to this, so thought would start one. Q: what should the compression be on a 3.5 with stock cam and pistons? The bluebook says (for a 3.0 obviously) 142-156 psi - another book i have on '88 535 says same - 142-156. Sven and I did (dry) compression tests on our cars today, mine were 148-152, his were 175-185. we thougt our motors were basically the same (although mine has more miles) but guess not. what should the numbers be?