Is it possible im getting better gas mileage by using gasoline with no 10 percent ethonol?

Question

the sticker is only on the regular pumps

Answer 1

I keep pretty good track of my mileage, and cant tell the difference between different brands and between 10% ethanol and straight gasoline. Supposedly though anything at 10% and less does not need to be labeled, so maybe all the stuff I use has ethanol in it.

Answer 2

Ethanol in fuel will result in a slightly higher octane rating, but a slightly lower heat rating. So it's a bit more resistant to knocking, but makes slightly less power.

The lower heat output can be offset by advancing timing to take advantage of ythe higher octane rating to give higher cylinder pressures and improve power output.

If your car is adjusted to take advantage of the ethanol fuel you won't notice a diffrerence in power over regular full strength fuel, but you may feel a slight increase in throttle response, and your fuel bill should be slightly less because ethanol fuel is supposed to be cheaper.