2.76 vs 2.94 gearing

1968 Dart 270 said
Wow! That's pretty good. I've always wondered if the feather duster really got the mileage they advertised

Stock cam, heavily ported head, stock valves. I may have been running a slant 2bbl Holley at the time. No power steering, not running the dealer installed AC.

70 with the AC on was 16.7.