BMW M4. The heat is the worst enemy in turbocharged engines, this is well known to all. The engineers of BMW M, then, resorted to a concept as simple as it is ingenious: a water injection system for the 6-cylinder biturbo the M4 so as to lower the temperature in the combustion chamber and maintain efficient the engine in case of hot (from 20 ° up).
This solution is applied to the BMW M4 Pace Car of the Moto GP and finished the season will be put into standard on M street. In essence, the principle of operation is as follows: in the luggage compartment of the M4 there are a reservoir of 5 liters of water, an electric pump and connected sensors to the management engine that decide when and how much water to inject.
Through dedicated ducts, water is injected in the form of a fine mist inside the combustion chamber. When the water evaporates, helping to cool the air drawn in by the engine, allowing the supercharger to work at maximum load. BMW system at a higher power by 8% (so they would from standard 431 hp to 465 hp), but also an equal reduction in consumption.