I have heard of a few attempts to utilize nitrous oxide in small engines. I seem to recall the old American Helicopters outfit in SoCal tried it for the engine used in their giant Atlas Van Lines Hydro boat before the company was destroyed by fire. There was a chap up here who tried it in a Webra .90 with completely disasterous results which ended in a cracked head. I think the problem would be metering the miniscule amounts of NO needed and at the right time; I believe even for large engines the amount needed is very small. The small tanks used for microflame torches would be just the right size....