Originally Posted by Chris b
just a word to the wise. if your running 93gas with 10%Ethonal I would run the 91tune just to be on the safe side with less knocking and pinging
Actually, you are safer running ethanol than non-ethanol if you are worried about knocking and pinging because it has a slower burn wave. You won't make the same power, but you are less likely to have detonation issues with the advanced timing of the 93 octane tune if you run an ethanol blend.