1.1 ,This specification covers the requirements for automotive fuel blends of ethanol and gasoline for use in ground vehicles equipped with ethanol fuel blend flexible-fuel spark-ignition engines. Fuel produced to this specification contains 51 ,% to 83 ,% by volume ethanol. This fuel is for use in flexible-fuel vehicles and is sometimes referred to at retail as “,Ethanol Flex-Fuel.”, Appendix X1 discusses the significance of the properties specified.