Flexible fuel vehicles (FFVs) are built to use gasoline or E85, a gasoline blend containing 51 percent to 83 percent ethanol, typically about 70 percent ethanol. Durable fuel system materials protect against metal corrosion and plastic deterioration and protect catalytic converter performance when using highly concentrated ethanol. Also, a computer in FFVs adjusts the fuel/air ratio level to accommodate high ethanol concentrations. FFVs are also equipped with special fuel injectors that have higher volume capacity (Reynolds, p.27).