750cfm too much?

IIRC the old 318 cop motors had Quadrajets and not Thermoquads on them. Similar layout, small primaries and large secondaries. Both had air valve secondaries which meant that they opened only when the right foot wanted it and the engine could accommodate more fuel.

Don't know about the Holley you mentioned. If it uses a vacuum secondary, it may work out. Otherwise, IMHO, you have some good trading material.

FWIW: My Demon runs a teen with a 625 cfm AFB on a Performer. Throttle response is good.

Someone recently posted some cfm ratings of muscle car carbs. They seem to be a lot less than I recall. See below.

http://www.forabodiesonly.com/mopar/showthread.php?t=285033&highlight=cfm+ratings