How did I miss this thread??? Musta been busy that summer. Tom, that is awesome mileage. My Gasolator predicted about 19mpg on a 75mph trip. Some more info, speed hurts - Gonkulator predicts the following MPG depending on cruise speed (prediction includes gas & rest stops) Speed.......Avg.MPG.trip 40......20.5 50......22.4 60......22.0 70......20.1 80......18.1 Some cars actually peak at 30 or 40mph (actually the Model A Ford gets its best MPG at about 25mph, we won the economy run one year with ours). But tall gears, good aero, and big cams favor higher speeds.
Surprised youre doing better than the Gasolator running a HOLLEY of all things. To me, this is confirmation that Holleys are good and efficient carbs when your foot is in them. EG, a lot of Ford trucks ran Holleys in the 70s. If they were gas pigs, Ford wouldnt have done that. But your foot is usually in the truck, so the Holley is quite efficient. The trick to me is that progressive conversion you did - so the 1bbl is open far enough to be efficient even as a Holley.
BTW have you had that ratty longroof to the strip yet? Gonkulator says 2.44 10.07 at 70.3 15.62 at 88.7 Thats pulling its full 3900lb.
I did find the two intakes as near equals as noted in past threads. But that was on a 3.08 powerglide, both a 250 and 292 in front. That did surprise me - the Clifford did not lose down low.
But, I would give it to the Offy for warmups - I didnt use the manifold heat, but even without that, theres just a lot of "floor" and slow moving air in that big Clifford. Probably the Offy is a better MPG choice especially in cold weather.
