Why does ethanol get worse mileage but still increases performance ?

Question

Hello,

When used in “regular” cars, ethanol (E85) tends to decrease the mileage compared to gazoline. This increased consumption suggests a lower energy density.

If that’s the case, why is ethanol used on tuned cars to increase their performance?

Thanks !

In: 2

Answer 1

Not suggests. It’s well known that ethanol has a lower energy density than gasoline. Like 75%.

Small amounts of ethanol help gas combustion because it burns so clean and provides some additional oxygen.