Don't do it! Ethanol is terribly corrosive and you should avoid it whenever possible. In the mid 1990s I worked for Siemens for several years as a fuel systems engineer for the OEM automotive market, and you would not believe the damage Ethanol does to fuel system components (o-ring seals, injector orifices, even metal sealing surfaces, etc.) It is a terrible idea to use Ethanol (even an E10 or E15 blend), and it is only used in the US because the Farm Lobby has donated sufficiently to politicians that they mandated its use.
I don't know if there's a power increase (the specific energy of Ethanol per unit volume is lower than gasoline, but it can tolerate more aggressive ignition mapping, so in some circumstances you probably could see a power boost), but that will likely be offset by increased maintenance costs replacing seals, injectors, etc.
Go to any boating forum, search "Ethanol", and you'll see what I mean. It tends to damage marine engines even more because they often sit unused longer than a typical car.