Lower-octane gasoline is blended with 10% ethanol to attain the standard 87 octane. Ethanol contains less energy per gallon than gasoline, to varying degrees, depending on the volume percentage of ethanol in the blend.

What octane is ethanol free gas?

Ethanol-free 90-octane gasoline is sometimes marketed as “recreational fuel” or REC-90. Many consumers prefer to use this pure gasoline that isn’t blended with ethanol for marine equipment and small engines for lawnmowers, snowblowers, chainsaws, generators, pumps, and the like.

Does 93 have ethanol in it?

All gasoline brands have both pure and ethanol-containing gasoline under the same brand names. For example, Shell V-Power ranges from 91 to 93 octane both with and without added ethanol. It just varies from station to station, and it’s up to the station owner whether or not to sell pure gas.