If you’re looking for better economy, try the new Edelbrock avs2 650 or one of the Street Demons.

I’m not sure how much better the mileage would have to be to justify buying a new carb, but imo if it improved the mileage by 1-2mpg....... you’d be doing pretty good.

68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads