The other thing that factors into this equation is the stoichiometric ratio required to combust the different fuels. The Air:Fuel ratio for gasoline is approximately 14.65, while the ratio for ethanol is 9.00.

This means we use 14.65/9.00 = 1.62 times as much ethanol operating at the same rpm setting.

Because we burn 1.62 times as much ethanol the power comes out SLIGHTLY greater in favor of pure ethanol, simply because of the increase in fuel burned.

This assumes burning straight gasoline vs. burning straight ethanol and is somewhat simplified of course.

You are correct with your last sentence as well. Ironically ethanol is very cheap to make from sugar cane, and we could import from Brazil cheaply, but Iowa 1) grows corn and 2) nominates presidents. The subsidies for domestic ethanol won't end any time soon...

I greatly appreciate the work of Matt, Ed, Todd, and others on this engine. I love flying pattern planes but don't like messing with/maintaining my YS engines, and I don't appreciate feeding them the 20/20 fuel or 30% heli fuel at over $30/gallon. This thread has provided me with a great amount of food for thought. I am looking at selling my several very nice YS engines to get a Syssa engine, plus the fuel savings over a season or two would cover all the cost of the ES pipe.

~Brett

p.s. the stoichiometric ratio for methanol is 6.0 I believe, which is part of the reason why a glow engine of similar size will produce more power than a gasoline engine, although it burns over twice the fuel in the same amount of time...