What I don't get about his formula, one it's not a cam formula just an LSA formula, two it's based on valve to cid ratio, think it would be cfm to cid if anything. A 2.02 valve could be just 360 head with a 2.02 slapped in to a trickflow +, pretty big difference. I'm sure a 360 or 408 gonna struggle to breath more with the former. Hard to believe you can just boil it down to valve size.