Used primarily in flexible-fuel vehicles designed specifically for high-alcohol content, this blend offers significant cooling benefits and high knock resistance. The 15 percent gasoline portion is necessary to ensure reliable cold starting and to make the invisible methanol flame visible in case of a fire. Engines running this fuel require substantially higher flow rates from injectors and fuel pumps.
The tune is set for M85, so make sure the wideband is reading the correct stoichiometric ratio.
Related terms
M15
A blended motor fuel consisting of 15 percent methanol and 85 percent standard gasoline.
E10
A motor fuel blend consisting of 10 percent ethanol and 90 percent gasoline.
B100
A motor vehicle fuel consisting entirely of pure biodiesel without any petroleum blend.
High-octane
A grade of gasoline formulated to resist premature detonation under heavy compression.