the edelbrock 750 is identical in venturi and throttle bore size to the '67 440hp carb; which wasn't none too big. only practical difference is air horn size. the '68 and up 440hp had slightly larger secondary venturi with the same throttle bore size. one of the mopar mags, mopar action i think, did a flow test on the larger '68 and up avs and i think they only got 715cfm. i seriously doubt the 750 edelbrock is near 750 cfm. probably 700 would be more accurate. another thing to keep in mind is that the '64 s/s wedges ran two carbs the same size as the edelbrock 750. i don't get lost in any of the cfm hype. it's more a marketing ploy anymore. the velocity controlled secondaries keep people out of trouble. the real key is calibration and to re-work afb's one has to get their head out of the holley box.