U.S. Carmakers Push for Higher-Octane Gasoline

The U.S. auto industry is lobbying Congress to hike the octane level of regular-grade gasoline and help them boost the efficiency of piston engines.

The coalition, working through the U.S. Council for Automotive Research, wants the U.S. to adopt the European standard for so-called 95 RON, a gasoline blend equivalent to 91-octane fuel, The Detroit News reports.

Today’s regular-grade gasoline has an octane rating of 87. That compares with about 89 for mid-grade fuel and 93 for premium gasoline.

Octane is a measure of a fuel’s ability to resist spontaneous combustion under pressure. The effect, called engine knock, disrupts the orderly combustion process, hurts operating efficient and can damage the engine. Making higher-octane fuel the norm would enable higher-compression powerplants that are more powerful and fuel efficient.

Carmakers estimate the change would improve average fuel economy about 3%. They also predict the current price gap between regular and premium grades—about 50 cents per gallon—would narrow to about 8 cents when higher-octane fuel becomes the standard.