Is a Holley 750 DP too much carb?

Some details about the engine would really help!
Off the cuff, a 750 is just fine for stock to a well prepped hot rod. A 750 covers almost all the bases. Unless it is a strip car or a seriously beefed up engine, 750 is perfect.
Ok here are the details about my engine:
Mains cut .010 Cylinders overbored .030. New cam bearings, Comp Cams Extreme energy cam. cam advance duration 274 intake, 286 exhaust. Cam duration at .05 230 intake, 236 exhaust, Cam lift valve .488 intake, .491 exhaust. Cam lobe separation 110 degrees. Cam degreed at 105,5 degrees.

Driveline: A833 23 spline transmission 4 speed, 83/4 inch rear end with a 3.91 gear.
The car runs great and launches hard. Just seems like it's really hard on gas. I'm getting about 6-7 miles per gallon. Does that sound right? Someone suggested to me that is too large a carb and maybe a 650 would be better. It does run great and I don't want to fix it if it aint broke.