Methanol vs Ethanol

With the IRL going to Ethanol next year they have opted to go back to the 3.5 L engine to make up for some of the power lost by switching from methanol to ethanol fuel.

Something called “latent heat of vaporization” is what is responsible for alcohols better than gasoline performance in racing engines. This is in spite of the fact that alcohol has less power per unit volume than gasoline. The Latent heat of vaporization is also what gives methanol the edge over ethanol even though ethanol has more power per unit volume than methanol.

So why the change to Ethanol? Obviously has nothing to do with performance, likely just a PR move!

For a good read on alcohol fuels: http://journeytoforever.org/biofuel_library/ethanol_manual/manual1-2.html