Twin-scroll turbocharging

The new four-cylinder engines also feature twin-scroll turbocharging. This means that the exhaust stream from cylinders 1 and 4, and the exhaust stream from cylinders 2 and 3, follow separate spiral-shaped paths to the turbine wheel. This reduces exhaust back-pressure at low engine rpm, allowing the energy of the exhaust gas pulses to be utilised as efficiently as possible. The result is instant throttle response and fast-revving performance which BMW drivers can instantly translate into driving pleasure.

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    Performance
    For 2009, there's just one engine: a 3.0-liter six-cylinder that's good for 260 horsepower. It teams with either a six-speed manual or a six-speed automatic transmission. All X3s have all-wheel dr ...

    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 ...

    Selecting menu items
    Menu items shown in white can be selected. 1. Turn the controller until the desired menu item is highlighted. 2. Press the controller. Menu items in the Owner's Manual In the Owner's Manual, ...