RE: Nitrous Oxide?
Nitrous oxide for 2 stroke glow engines is a complete joke. Don't waste your time, money buying the kit, and money fixing your boat from using the kit. Nitrous falls int he same catagory as a turbo charger or supercharger for these types of engines. They just don't belong. It's nothing more than a "wow hey guys look what I've got".
Getting the nitrous system to work in a glow engine is nothing short of a wild crap-shot in the dark.
Do yourself a favor and upgrade in other, more usable areas, like getting your engine tuned right, upgrading to a better tuned pipe, or just getting your boat set up properly as a whole. If then you still aren't satisfied with the results, upgrade your engine and prop.