Now that my Fairlane is finally running reliably, I have been driving it to and from work all week. The drive is a mixed bag with most of the miles being lightly hilly country roads at 50-60 mph, with some city/stop and go at one end, a brief stretch at 65-70 and a couple of lights in between. It's about 34 miles one way. I have averaged 11.8 MPG on that route, which seems several points low based on what I've read here and what my 292-equipped '59 Galaxie used to do (15-18).

Mechanically, compression is good, engine is stock 312 with stock cam (believed original to car with 85k miles). Timing chain is new, carburetor is stock Carter AFB, trans is FOM, 3.10 rear axle. Distributor is original, vacuum advance is new with old internals swapped in (though they could easily have been changed since the factory), 10* initial timing. I have been using regular gas (e10, really, as that's all that's sold here) because there hasn't been any spark knock so why pay for premium?

I'm pretty sure I don't have any brake dragging but I will check it tomorrow. Also, the front end is worn out so the alignment could be adversely affecting mileage to some degree. I have pulled and checked different spark plugs at various times and they all look clean with some darkish brown color on one side of the insulator and a pink tint on the rest of the insulator.

I have a '57 Autolite 4100 in need of some repair and a rebuild kit. Do you think that the 4100 would give significantly different mileage than the AFB, if set up with stock jetting?

Based on what I've said, would time be better spent playing with carbs or recurving the distributor?

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive