"What does it do to plastic or rubber seals?"
http://www.foxvalleykart.com/fuel4.html
There are a couple of chemicals in the Nitroparaffin family that are of some interest as oxygenators. Methyl Ethyl Ketone (C2
H5 COCH3), often referred to as MEK, appears on the surface to be an attractive oxygenator. A commonly used industrial solvent, MEK has the unfortunate property of consuming all its own oxygen during its own combustion, leaving none to benefit the remaining combustion process. Coupled with its relatively low specific energy, it's basically a waste of time.
The same goes for Acetone (C3 H6 O), whose relatively meager supply of oxygen isn't even sufficient to support its own combustion, much less lend any to the gasoline reaction. Acetone does have one attractive property, however. It is extremely hydroscopic, meaning that it attracts and absorbs water. In the old days, the McCulloch racers knew this and used to mix acetone with their alcohol to help suspend the moisture that the alcohol attracted and put it in a more combustible form. It will do this in gasoline as well and, since water is not soluble in gasoline at all, but acetone, even acetone that has absorbed some water, is soluble in gasoline, it's a good way to deal with water-contaminated gasoline. But there's no power advantage to be had here and, if you're having a problem with water in your gasoline, you don't need a chemical to fix it. You need a better gasoline supplier. By the way, ketones like MEK and Acetone are also really hard on rubber and plastic parts, like carb diaphragms, etc. In concentrations of less than about 15 percent by volume, it is impossible to see any change in the combustion process, while anything over 10 percent may dissolve your metering diaphragm before the day is done. Sounds like a bad bargain.
Are you talking about go-carts when you talk about McCullochs?