I'm A gas man by trade and have thought about propane injection for years. I have always thought that it whould be a great enrichment fuel for NOS. All you would have to do is get a fork lift or flore buffer tank(they come in aluminum and have liquid ports), And a solinoid. You no longer need a exotic fuel system. You would have to figure out the orifice size. Propane works like NO it sets in the tank as liquid and makes its own pressure. When With a boiling point of -44 it would add to the cooling effect of the nitous. I'm not sure that you can inject enought into the cylinder without nitrous to achieve those boost numbers, but the cooling effect (44 degrees below zero) could be exploited for some exta HP. All we need now is a willing test subject