if you're doing a motor / driveline these will help

ABOUT DISPLACEMENT, VOLUMETRIC (VE) EFFICIENCY, AND CFM
http://www.edelbrock.com/automotive_...disc_cfm.shtml

ABOUT COMPRESSION RATIO
http://www.edelbrock.com/automotive_...mp_ratio.shtml

COMPUTING HP AND TORQUE
http://www.edelbrock.com/automotive_..._disc_hp.shtml

It's no big secret dispite what most mechanics will try to make you believe

Cubes x rpm x compression = X hp (providing the VE is correct)

Just like ETs. If you dont have the correct ratios / tyre size etc 2million hp wont do shit

math is everything