Running high octane (110 -115) gas will not increase horsepower in an engine with lower compression. It will actually lose horsepower. Higher octane gas burns slower. You need the high compression to burn that properly. On a standard compression engine, pump gas will work better than 115. I cannot speak about 93 octane race gas. Fuel can change engine temps. For example, pure ethanol burns very clean and cool. The down fall is that ethanol burns fuel significantly more than gas. Ethanol (pure) also has no lubricating properties (thus more rebuilds) and additives have to be added prior to or after purchase. I wish we could use E-85, you gain horsepower, while having the energy and some of the lubricating properties of gas. The horsepower gain is significant.
