can be useful if you only require short bursts power.
Run the refrigeration when the engine is at part throttle to chill down a tank of coolant.
Now what is highly dangerous, illegal, difficult to tune and does work well is if you have an LPG engine and you use a special Tx valve to spray liquid LPG into the inlet manifold. cools better than methanol. They tend to blow up in various ways and don't go for long. Don't try it.