Twin-scroll turbocharging

BMW 3 Series / Overview / 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.

    See also:

    Measurement
    Measurements are made by ultrasound sensors in the bumpers. The range is approx. 6 ft/2 m. An acoustic warning is first given: By the front* sensors and the two rear corner sensors at appro ...

    Features
    The 2009 X3 starts at $39,700 and comes standard with leatherette upholstery, eight-way power front seats, a panoramic moonroof and rain-sensing windshield wipers. There are four option packages a ...

    Malfunction
    In the event of a malfunction, the steering wheel must be turned further, while the vehicle responds more sensitively to steering wheel movements in the higher speed range. The stability-enhanc ...