[Frank Messina]

Your mileage seems low with that engine. But with the 3.73 rear gears, spending a lot of time in fourth gear will kill mileage fast. Are you running vacuum advance? If not that's another thing that will hurt gas mileage. Hook up the cannister on the distributor to a manifold vacuum source on the carb. This will give about 7° additional advance at off idle and part throttle cruise. ( it's adjustable with a 3/32 Allen wrench) Throttle response will go up along with a nice bump in mileage. Contrary to what else you hear, don't bother using the timed port on the carb. That's a no performance smog hookup. HTH