Unless you have a high dollar set of pistons that you absolutely MUST use on this build, I wouldn't even worry about it. The HP gain from a handful of inches is no where worth the headache you could create for yourself. Just cram a bunch of compression in the motor and a some GOOD parts in the valvetrain and let her rip. I love hearing those old small cubic inch motors screaming at 8000+ rpm. Ya gotta love it. It makes me reminisce about times that were before my time :?