davepl

Does anyone know what the normal cranking compression on an LT1 is?

My 396 with 9.0:1 is turning out about 155psi, I'm just curious how that compares to the 10.5:1 stock motors. I have a 236/236 cam which may be bleeding off a lot of cranking compression, even though its on 114 centers.

Also, how much variance is "ok" on a motor? If I have 157 on one and 152 on another, should I be upset?

Thanks,
Dave

R_Andersen

Well, for comparison, my 383 with 11.3:1 compression with the high lift 230/236 cam had 200-205 psi cold cranking compression when it was new.... 10% variance is usually acceptable but a fresh motor should probably have less variation than that..

-Rob