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 and convertible. The standard eight-speed automatic transmission includes steering-wheel-mounted shift paddles.

Other standard features include computer-controlled adaptive shock absorbers and Driving Dynamics Control, which allows the driver to adjust the ride quality, accelerator response, power-steering assist level and automatic transmission behavior.

Optional mechanical upgrades include active stabilizer bars and active steering, the latter of which adds rear-wheel steering to the earlier generation's variable-ratio front steering system.

    See also:

    Active seat
    Active seat The seat cushion is actively varied by alternately raising and lowering the right and left half of the seat cushion. This reduces muscular tension and fatigue to help prevent lowe ...

    Signal tones
    When approaching an object, an intermittent tone is sounded that indicates the position of the object. For example, if an object is detected to the left rear of the vehicle, a signal tone sounds ...

    System limits
    Sudden tire damage Sudden serious tire damage caused by external influences cannot be indicated in advance. A natural, even pressure loss in all four tires cannot be detected. Therefore, check ...