Besides what camaroman7d said, you're measuring cranking pressures. They are different then compression ratio and is not a valid way to determine CR. Cranking pressure have an awful lot to do with cam timing. You could have a 7.5 CR motor make higher cranking compression then a 11:1 motor! All cam timing. It's also important to put 2 & 2 together and realize that with a mild cam timing that a 7.5 motor uses to create high cranking pressure would be disasterous in a motor with 11:1. You'd create stratospheric pressures that would diesel the motor. Conversly is true also, meaning a cam intended for a 11:1 motor would cause such low cranking pressures that the car would be even more of a dog on low end. This is why cam manufacturers tell you what kinda mechanical ratios to run on their cams.