My stats were at altitude (6,800'-10,300'). Some compression braking. 14.7mpg. I'm using the larger (sea-level) jets that came with the carb. 4.11s, 28-inch treads.
I have ambitions of getting as much of the smog stuff back in service, and/or the motor looking or operating like a North American model again, which is better than all of those parts taking up space in storage. So, I'd want to use MPG as a crude measure of power-output, before and after.
Maybe it is a lack of acoustic insulation, but, when it sounds like a sewing machine, the throttle is always really responsive, and the block and carburetor are always warm. I know that cold really reduces fuel range, and it creates a roughness to the idle, like almost half (8mpg). My spark plugs foul easily, so I'm always thinking about congestion removal in the combustion chamber, and at the rings, with fuel additives - certainly reducing any pre-ignition causes can help power output. Perhaps, I should rebuild the original 2F that it came with, keeping it all numbers and vintage correct?
I'm fairly certain that a motor's life is cut short by running lean (burnt exhaust valves), or running rich (fuel dilution of crankcase oil, or inconsistent spark due to carbon fouling). Both conditions would likely reduce mpg. I'd consider MPG as good as a vacuum or compression test as an indicator of engine performance, especially if it was for sale, with or without the car.
