If I was to figure how much cfm needed for say a 365 @ 6500 rpm with my monkey math (left to right) 365 x 1.25 x .9 x 6500 / 5252 / 1.8 = 282 cfm vs 365 x 6500 x 0.0009785 / 8 = 290 cfm.
So basically the same (282 vs 290 cfm) but mine is figured by a lot less efficient engine 1.25 x .9 is guesstimated peak lbs-ft per cid times 90% of torque at peak hp and only making 1.8 hp per cfm. But what confuses me is their formula is based off 124% VE which most engines are gonna fall way short of but even with the high VE% it really don't calculate an ridiculous cfm amount though.