I can shed a little light on the effects of water in the fuel, since it was one of the components ot the methanol/peroxide mix my family used in the dirt tracker for a lot of years. We ran a mix of 75% straight Methanol and 20% technical-grade peroxide, with 5% amyl acetate as a wetting agent. Medicinal-use peroxide is 2% by volume, with the remaining 98% being plain old water. Hair-bleaching peroxide is strong stuff, a 4% concentration. Ours was 20% strength. Depending on humidity, we would add 1,2, or 3 6-ounce Coke bottles of straight water to an 8-gallon fuel tank and jump up and down on the back bumper to mix it. Dry day, more water! Alcohol and water will mix in any proportion, so the water would distribute itself equally throughout the fuel tank. In the combustion chamber, the water would flash to steam, keeping the combustion cool enough not to melt the pistons. Running without the water resulted in erosion of the piston crown above the top compression ring.
Peroxide is CORROSIVE! Our fuel tank was an 8-gallon stainless steel beer keg, with all-stainless fuel lines to the carburetor. Every time we stopped the engine, it was necessary to turn off the fuel and run the carburetor dry, to keep the fuel mix from eating holes in the aluminum float bowl. A carb rebuild lasted exactly one night of racing, so we had to build a fresh carb every week. In a matter of a few minutes, fuel left in the float bowl would turn a chocolate brown color from chemical reaction with the aluminum.
The old 34 Ford 3-window coupe ran like a turpentined cat, with a compression ratio of around 11:1, and approached 6,000 RPM with a 4 1/8" stroke, but the engines were very short-life affairs, maybe half a racing season!
Jerry
Last edited by Hotrod Lincoln; 09/06/2008 7:08 PM.
