If you're hauling the mail (90-95mph), it averages about 16.5mpg. At more normal highway speeds, 17-18 (the best I've ever gotten was 19.2). Chalk that up to a big overdrive (.64), mild gears (350's), and a well tuned edelbrock (the holleys may make more power, but MAN do they drink gas). The thing just LOVES the highway (see the pic).
On the other hand, when you're having fun (like climbing the poudre canyon, for example), mileage drops to a more predictable 10-12.
I figure the gas cost me about $1000 round trip, but it sure beats flying and there's no restriction on liquids, if you know what I mean...
This is just a demonstration of driveability. The Speedo is a bit optimistic, but this is still 90mph at 2600rpm.
1967 Galaxie XL, Q-code, 428"
1994 Bronco, 5.0L (winter car)
1972 Triumph TR6 (soon to be ford stroker powered)