Alcohol fuels burn faster than straight gasoline but the burn speed depends on the mixture as well.
Gasoline has its highest burn speed near 11.3:1 AFR
Max burn speed for ethanol and methanol fuels are at even richer mixtures. The higher burn speed of ethanol is one of the reasons E85 is more effecient than gasoline (aside from octane and charge air cooling).
That is also one of the reasons 50:50 water methanol WI needs less ignition advance than plain water.
http://www.epa.gov/otaq/presentation...mjb-051303.pdf
Check out the chart on page 9
Larry