Well, for our purposes, alcohol has a high octane rating. Using the (RON+MON)/2 method (the number you see at the pump) alcohol comes up at 99.5 for ethanol and 99 for methanol. This allows us to run higher compression than you normally would with a gasoline engine and compression is power! As an added bonus, alcohol burns much cooler than gasoline further aiding in detonation resistance. In fact some drag only cars that run alcohol will completely fill the water jackets with Hard Block and don't run a cooling system at all! On the green side of things, alcohol burns very clean thus reducing tailpipe emissions. Of course with the good comes a price. Alcohol is extremely corrosive, so care must be taken when selecting fuel delivery components. A standard Holley carburetor requires a good deal of modification to run alcohol. Alcohol only contains about 63% of the energy that gasoline does, so we have to run almost double the amount of fuel. Alcohol will not ignite with a spark from the ignition system, so cars running 100% alcohol must be primed with a more volatile substance in order to start, hence E85, 85% alcohol, 15% gasoline. Well that's all I can think of for now, but I hope it helps!