one thing to point out, there will be a point where heated fuel might work against you
with the new 4 stroke motocross bikes, the ambient heat from the engine can heaet the gas in the plastic and carb that it boils in the carb, and theyve had significant problems with the engines failing to run right after the fuel begins to boil. Bikes have been known to misfire and even flame out on decel. I doubt the fuel temps in the carb are much over 200 degrees F.
*Im just guessing, but id say to a point, warmer fuel might get better mileage, but there would be a point where it would start to work backwards without a significant redsign of the fuel system. Most fuel systems are designed to work with a liquid fuel, and to take advanage of heated fuel, they would need to work well with a fuel in gas form.
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