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:

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    1 Series M
    Rather than the single-turbo setup from the 135i, the 1 Series M gets a twin-turbo six-cylinder that's good for 335 hp and 332 pounds-feet of torque. In extreme situations, the 1 Series M can ente ...

    Ventilation in rear, center
    Thumbwheels* for adjusting the temperature, arrows 1. Toward blue: colder. Toward red: warmer. Lever for changing the air flow direction, arrow 2. Thumbwheels for opening and closin ...