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Close the windows and glass sunroof
Driving with the glass sunroof and windows open results in increased air resistance and raises fuel consumption. ...

Under the Hood
The 640i is powered by a 315-horsepower, turbocharged 3.0-liter six-cylinder engine. Its peak torque rating is 332 pounds-feet. BMW cites a zero to 60 mph time of 5.5 seconds for both the coupe an ...

The concept
The system is functional at speeds beginning at approx. 20 mph/30 km/h. It maintains the speed that was set using the control elements on the steering wheel. The system brakes on downhill gradie ...