I've done some "E-search" on this subject and this is what I'm thinking about doing.

The Twin Cam in my 01 FXDX is bored to 95 inches with 10.5:1 domed pistons, stainless valves with race springs, .625 cams and a programable ignition. Currently, the timing is set way back to keep the engine from pinging on the 91 octane pump pi$$ that is the best we can buy here in So Cal.

I want to re-jet the S&S carb, bump the timing up, and run E85.

The E85 is a mix of 85% ethanol and 15% petroleum distilliates (aka., "gasoline"). Ethanol has a higher octane rating than petroleum distillated gasoline (i.e., resistance to auto-ignition under pressure at high temperature) but it has a lower energy content.

My plan is to put bigger jets in the carb so it delivers more fuel (about 30% more) and load a new timing curve in the ignition. By running the E85, I should be able to take advantage of the high compression that the bored out twin cam is making.

I know that the ethanol will tend to eat through the fuel line and, because it can carry moisture, may tend to let the steel tank oxidize. The ethanol may be a little rough on the S&S carb and I won't get very good mileage but I think being able to get the performance out of my over-built twin cam will be worth it.

Any thoughts, suggestions, tips?