The crossfire should run on e-85, but the question is if the fuel system will hold up. 85% ethanol will be very corrosive to the fuel system. A GM rep i talked to said the fuel system must be stainless to standup to the corrosive nature of ethanol. I don't know anything about the xfire fuel system so I don't know well the car will run/hold up to e-85. ps. don't drink the e85, i think the other 15% is gasoline...