Originally Posted By: Boomer
Alcohols actually have very high octane ratings...remember the methanol fueled Offenhauser engine? And while there are corrosion problems from ethanol in gas and water attraction issues, ethanol actually burns pretty cleanly. So I am not sure where you are getting the carbon buildup in the manifold, etc from burning ethanol.
You're right - pure alcohols are excellent fuels. I remember back in the day grass-track 500cc motorcycles would run on pure methanol and castor bean oil pumping out 50 hp+, but need frequent teardown and cleaning, mostly because of oil deposits.
Ethanol is an octane booster, but the consensus appears to be oxygenated fuels like E-10 gasoline BLENDS are more prone to carbon buildup, especially when contaminated with water. This is supposedly why gasoline manufacturers developed nitrogenated amine additives (Chevron, Shell.) I don't have the reference and technical explanation to hand right now.
Best bet is to read the MSDS of any fuel additive to see if there really are functional ingredients worth your money beyond simple diluents like stoddard solvent or alcohol. Poly ether amine in the right amount is proven to minimize carbon deposits.