i know alot of fords are setup to run off of gas and Ethanol with a 96 ford contour zetec run off the Ethanol without modification
if your talking about the bi-fuel contours they can run off of gasoline or compressed natural gas (CNG). E-85 is a type of fuel that is 85% ethenol, normal gas is only 5-10% ethenol
as for running a normal gas car off of E-85 it is not recomended as the E-85 has a tendancy to eat through seals and gaskets in wehicles that were not designed for it.