It's not too hard to get good gas mileage on open roads. A few years ago me and my girlfriend drove a 2001 Honda Insight 1040 miles on one 12 gallon tank. (85

It's not too hard to get good gas mileage on open roads. A few years ago me and my girlfriend drove a 2001 Honda Insight 1040 miles on one 12 gallon tank. (85mpg - fully loaded with luggage + nasty traffic.) In the Tour De Sol rally, we got 94mpg. Keep in mind it is a stock car and there was a lot of weight we could have removed. (AC, second person, interior, hybrid parts, spare tire, air bags, glass, etc.) We also only came in second place. The car is truly light (1850 lbs), but weight mostly affects rolling resistance (unless you hit brakes). With a lighter car, you can use a smaller engine. Though, around the same time I drove an 80s sedan with a v8 engine several hundred miles on the open road and got 40 mpg. It was so loaded down I mostly drove 50-55mph. For open roads, aerodynamics is everything. 80% of the energy is spent moving the wind at highway speeds. Even hills aren't a problem (they store energy like batteries). Perhaps cars could look more like airplanes? Then we could go 80mph and still get good mpg. Also, I find it curious that you need to modify a car to make it "safe" for use on a race track. They have insurance policies that require cages, fire suppression, rigid seats, 6 point belts, air bags removed, etc. They still tend to be quite light.