[Pyrotechnic]

7 MPG.....

Something is WRONG. What you have sounds perfectly streetable. I run a wilder motor on the street than you do and get 14-15 MPG while doing it. Others here have reported similar results from their 383's.

If you are having questionable driveability and that bad of gas mileage, I'm going to wager that there is something causing the motor to run badly. The combination itself should be fairly tame and streetable.

Things as simple as retarded timing, timing curve in distributor too slow, vacuum advance set wrong, carb too rich, carb flooding, vacuum leak, etc will all cause this kind of behavior.

Can you give us a detailed parts break down ? What kind of timing are you running ? Have you jetted the carb or did you just bolt it on ?