Lookinf for Carb Suggestions

I've got a 70 Duster 340 4spd. The engine is an older build running a Direct Connection Hemi Grind Purple cam (284-284-60 .471 int. and .474 ex.) I'm currently running a carb off a 1967 440 on top of an Edelbrock Performer.

The power is good but seems like it could be more. Throttle response doesn't seem to be what it could. From what I've read this is a 750 cfm carburator and the original would have been an 850 cfm. The carburator has a narrower throat than normal for this engine. At idle the engine seems to load up with fuel and smells super rich.

Would it be better off to go with a new Edelbrock or back to the factory carb? How big do I go with the carb? Any input is greatly appreciated.:yawinkle: