Bingo. If peak torque at WOT was the only thing that mattered - and that's almost always the only throttle position it's measured at - just dropping down a gear or two should improve mileage, right? We could all be driving PowerFlite 2-speeds or manual 3-speeds with 2.93 cogs. Again, I don't have any documents to back me up, but I think a lot more fuel is used with every turn of the crank than there is by changing the BSFC some small percentage. With all else being equal, an engine will use 50% more fuel at 4500rpm than it will at 3000rpm.

I think one thing that's killing mileage on many new cars is that they're big, fat, heavy, pigs chock-full-o creature comforts that Average Joe thinks he needs because some corporate marketing wonk told him he did. Take out some of the cruddy worthless "features" of new cars and they'd get a lot lighter. Reducing unsprung weight, like giant, heavy bLiNg rImZ , will make any vehicle perform better instantly in almost every respect, including mileage.

Another thing that hurts new cars is that they pretty much HAVE to stick to 14.7:1 AFR to keep the catalytic converters happy for a long time. Steady-state highway cruising really can tolerate much leaner mixtures, but converters don't work well there, and I think it's NOX emissions that go up when it's lean. If you can tune your carb to pull 16-17:1 at high-vacuum cruise, you can really bump mileage up. GM did this in the late-80's & early-90's EFI systems, but had to disable the code for emissions reasons. The code is still in the GM computers, so I'm planning on enabling that feature when I get my tune better. Going from 14.7 to a conservative 16:1 is an 8.8% improvement right there. If you're getting 15mpg, now you're at 16.3mpg. If you're getting 25, now you're getting 27.2. That's a noticible improvement. Going to 17:1 is a 15.6% improvement...

Oh, and before I forget, that's dang good mileage for that little car so far. I can't wait to see how it does once the carb and ignition are better sorted out.

Clair