The BMW M4 MotoGP Safety Car certainly looks super-sinister with its matte black paint, but that is not its stand out feature.
That honor goes to the prototype water-injection system designed to give the turbocharged straight-six a “noticeable boost” in performance, and which according to BMW, will soon finds its way into the firm’s M production cars.
Speaking at the brand’s press conference in Geneva earlier today, BMW CEO Norbert Reithofer said:
“For the very first time, this car applies our innovative water injection technology. Yes, you heard me correctly – water. The injected water spray cools the intake air and provides a significant increase in performance. At the same time, it reduces fuel consumption and emissions. This is BMW EfficientDynamics!”
BMW explained that the system makes it possible to raise the engine’s upper performance limits, which have otherwise been restricted thermally.
“Water is injected into the intake module’s collector as a fine spray, thus significantly cooling the exhaust air during vaporisation. This lowers the discharge temperature in the combustion changer and thus reduces the tendency for knocking. The turbo engine can thus be operated with a higher charging pressure and an earlier ignition point,” said BMW.
The system includes three injection valves in the plenum chamber, each supplying two cylinders of the inline-six engine, and a five-liter water tank housed in the boot together with the water pump, sensors and valve, all of which are controlled by the engine’s updated electronics.
One drawback, or rather, inconvenience, of the current system is that users will have to refill the tank with water.
“In rigorous action out on the racetrack, it is always necessary to refill the water supply whenever the car must refuel,” said BMW. “During standard operation, the intervals between water refills are considerably longer, depending on the driving style. Even when driving faster on the motorway, it is only necessary to refill the water container roughly every five stops for refueling. To ensure the system is as suitable as possible for daily use, it does not require any additional maintenance.”
Reithofer said that the system will soon become available on BMW’s M performance cars, though, he did not provide a specific timeframe.