BMW presented a liquid-cooled 1.5 liter three cylinder engine. The engine uses the same system as that of the M4 for Moto GP and it produces 218 hp, while it makes a direct injection of water into the combustion chamber, reducing this way the temperature and consumption and increasing the efficiency and the horsepower.
The more efficient combustion process, reduces the combustion temperature. According to BMW the system reduces fuel consumption by 8%, and improves performance by 10%. The required water is stored in a tank of about 4 liters, properly insulated from frost, located in the luggage compartment with the water pump, sensors and valves to be controlled by the car. The pump, feeds the water injectors with a pressure of 10 bar, while the volume of water supplied depends on the load, engine speed and temperature, in order to obtain optimal water consumption. BMW says that the water tank must be refilled once a year, or more often if the air conditioning system, is not used much.
