My home inspection of Speedmaster heads

What kind of compression numbers do you think we will get? My 70 318 is supposed to have around 9:1 although that's just a number Ma Mopar came up with. I ran some numbers on the Desktop Dyno which can be a bit skewed, but with 340 manifolds and a Hughes Rattler cam I traded for, I came up with 380 horse and 460 lb/ft of torque. I used the head flow numbers found in another thread. (somewhere) I hope I bookmarked them.