• Models > 4-series > [F3x] > B4 S BiTurbo
  • [F3x]
  • B4 BiTurbo B4 S BiTurbo B4 S BiTurbo Edition 99 D4 BiTurbo
  • Introduction

    The B4 S BiTurbo is based on the BMW 440i. The B4 S BiTurbo replaces the B4 BiTurbo.

    In line with the new naming conventions at BMW, from the F30-series onwards the Cabrio and Coupe versions of the B3 S BiTurbo are named B4 S BiTurbo.

    In March 2017, at the Geneva motorshow, the B4 S BiTurbo was introduced in Cabrio and Coupe versions. At the same time, the 4WD version – the B4 S Coupe Allrad – was introduced.

    Production of the B4 S BiTurbo ended in late 2018.

    In 2019, Alpina offered a special version of the B4 S BiTurbo, the limited production B4 S BiTurbo Edition 99.


    The B4 S BiTurbo engine is based on the BMW 435i engine, which has been modified to 440hp and 660Nm.

    In comparison to the B4 BiTurbo, the turbocharger setup has been modified incorporating two new Alpina-specific turbochargers. Additionally, the piston crown cooling system has been modified. The external water cooler has 15% increased capacity, the external oil cooler has 35% increased capacity.

    The stainless steel exhaust system, developed in conjunction with Akrapovič, features two elliptical twin tailpipes. Exhaust sound is controlled by an intelligent exhaust valve linked to the Drive Experience Control button. In Sport Mode, the exhuast valve is permanently open.

    The only available gearbox is the 8-speed Sport-Automatic transmission (ZF 8HP70) with Switchtronic. Automatic up-shift function can be disabled using the Drive Experience Control button.

    Optionally, a Drexler limited slip differential is available.


    The B4 BiTurbo has adaptive M sport suspension with electronically adjustable dampers, performance springs, bump stops and stabilisers. The suspension is modified with Alpina settings. These settings can be selected using the Drive Experience Control button.

    Wheels are 20-inch Alpina Classic with 245/30 and 265/30 Michelin Pilot Sport 4 S tires. For winter conditions, 19-inch Alpina Classic wheels with 245/35 Continental ContiWinterContact TS 830 P winter tires are available.

    As an option forged 20-inch Alpina Classic wheels are available. They are similar in style to the G3x B5 BiTurbo.

    Brakes are same as the B4 BiTurbo.


    The B4 S BiTurbo undergoes the same interior and exterior changes as the B4 BiTurbo.


    Acceleration from 0-100kph is 4,2 seconds for the B4 S BiTurbo, for the B4 S Coupe Allrad 3,9 seconds.

    Topspeed is 304kph for the Cabrio and 306kph for the Coupe version.