Jerry - I agree completely on the Q-Jet; and in fact, Pontiac used a Q-Jet on their 230 CID and 250 CID OHC 6 cylinders.

However, it is sometimes difficult to explain primary CFM and secondary CFM to someone that asks "if 600 is way too big, why isn't 750 even more too big?".

CFM ratings

Carburetor selection

Probably the biggest issue in many trying to use a Q-Jet is that Rochester NEVER sold them as aftermarket, thus not a lot of information (exception: books by Doug Roe, and later Cliff Ruggles), and not a lot of aftermarket tuning parts availability.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop