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.

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