BMW to bring new 2.0-liter turbocharged four-cylinder

(January 29, 2011) WOODCLIFF LAKE, N.J. — BMW announced the return of a four-cylinder engine to the U.S. BMW line-up for the first time in since 1999.

Like the company’s latest 3.0-liter turbo inline six, the new 2.0-liter engine will combine twin-scroll turbocharging with high-pressure direct-injection and BMW’s Valvetronic intake control.

With 240 horsepower and 260 lb-ft of torque, it offers more power and torque than BMW’s normally aspirated 3.0-liter inline six. It will arrive later in 2011.

Maximum output of 240 horsepower is achieved at 5,000 rpm, 1,500 rpm lower than in the normally-aspirated 3.0-liter inline six. The peak torque of 260 lb-ft comes on stream at just 1,250 rpm. The engine with its all-aluminum crankcase is lighter and more compact than a six-cylinder engine of equivalent power.

The direct-injection system also helps to improve efficiency. Centrally positioned between the valves, solenoid injectors with a maximum injection pressure of 2,900 psi precisely control the supply of fuel. The fuel is injected very close to the spark plug, resulting in clean and homogeneous combustion.

The cooling effect of the injected fuel also allows for a higher compression ratio than might otherwise be possible. This results in further efficiency improvements.

US-specific model and timing information will follow at a later date.