That was a thought/concern of mine also... Looking at some of the dyno sheets on Hondata they recommend 91 or higher octane same thing w/the dyno sheets using KTuner.I have been thinking of the Hondata Flash offering. Don't relish the thought of having to go back to Premium Gas as that was a welcome relief from my other cars. Will have to read up some more or call them up. It's a relatively cheap mod for what it will do. Right now I'm just starting to explore the performance capabilities as it's just passed the break-in period.