Water / Methanol Injection injects a mixture of water and methanol into the system in turbo diesel engines. This allows you to reduce the EGT temperature while allowing you to safely increase the boost. It gives us more power and torque at a much lower cost than modification of a diesel engine, taking into account e.g. propane injections, nitrous oxide injection, IC upgrades, etc.
More precisely - the injection of the mixture contributes to the reduction of the air intake temperature and the suppression of detonation. The highly atomized water / methanol mist is injected into the intake air stream where it immediately begins to vaporize. The temperature is rapidly reduced by evaporation of the cold, then the liquid changes state under the influence of temperature and turns into water vapor. It's a 'liquid intercooler', the effect can reduce the temperature of the inlet air by as much as 100 ° F (~ 38 ° C) or more! The cooler, thanks to the denser air, provides more oxygen, which allows you to burn more fuel and give more power. An air cooler will also increase the knock threshold reducing the chance of pre-ignition and detonation.
Combining water and methanol can greatly increase anti-knock efficiency, allowing for higher compression pressures and longer ignition times. The water absorbs the heat which allows the excessive combustion temperature to be reduced and hence to lower the combustion rate.