That's bad. Regardless of chip tuning, E-85 will royally doink up the fuel system of a non-Flex vehicle. Think stainless steel plumbing from back to front.
Likewise, most Flex-Fuel vehicles, including my own, have a Fuel Composition sensor that determines what's coming out of the tank, from straight E-85 to straight gasoline, as well as the amount of water in that mix. The real-time signal remaps the ignition and injection timing for the blend coming through the injector rails. (Top off 1/2 tank of gasoline with 1/2 tank of E-85, and the system makes amends for it...)