With $4 gas, what do you get for mileage??????

'79 Magnum, current daily driver. Equiped with a 400 B block, 727, 9-1/4 3.55's and 235/60/15's (26 inch tires) with a weight of approx. 3800 or so when empty. 4,000 lbs. for sure when full.

9 around town, 13 Hwy. at best and goin easy. Theres no mileage with this stocker. Headers are the only addition and the replacement 4bbl being a Carter 750.

Looking foward to the Duster and 318. A '79 engine with a Crane cam advertised @ 272/284 - .454 /.480 lift, headers & 4bbl. Rear is a 3.21.

Any guess on my dusters mileage?