I'm on the low end of the spectrum, why, I can't figure out. 3.90 rear, stock 235 (Rochester carb., stock manifolds, Pertronix for sparks) 235/75R-15 tires, three on the tree tranny.
I've tracked every fill up the last year, mostly get mileage in the 11's with an occasional 12. This is with roughly 2/3's flat highway, 1/3 around town driving. I'm going 170-180 miles between fill ups.