Anti Detonation Injection - Its main purpose is to prevent engine knocking ( detonation combustion ) and premature ignition. At low altitudes it has secondary effect of increasing manifold pressure ( cool air = more dense ) Principle is: Water has the highest specific heat capacity of all common substances 4180 J/(kg·K). But that's not the most important thing. The most important thing is that in order for water to turn into steam, it needs an additional 2257 kJ/kg of heat. This allows it to cool the engine much more efficiently than a rich fuel mixture, because aviation fuel has almost half the specific heat capacity of water.
In my opinion it is not simulated yet. Because I think there should be "jump" in power at low altitudes, just like in P-47.