Station nearby +/- (Unocal 76 Agoura Hills) offers 100 octane unleaded racing fuel. Haven't dared it yet, so thought I'd ask the board what anyone may know about using it undiluted or blending to top tier on-the-road fuels. Thread from 2005 on the M5 side located 95 octane in Newport, but I can't find a technical discussion. My guess is the M6 will love it, and the Dinan I ECU flash can't hurt. Biggest question is whether there is any mechanical threat or warranty exposure. I would think this engine thrives on a high end fuel...and assumption is that it is a far cleaner burn and higher specific btu/unit=power uptick. Is this like a refined Bordeaux or backwoods white lightning?