The new performance saloon is powered by a 454bhp twin-turbocharged 3.0-litre in-line six and follows the M4 CS, with which it shares much of its mechanical package. The M3 CS will be available to order in the UK in January 2018; deliveries will be due after a planned start to production in March.
Building on the developments used on the M3 Competition Package, the M3 CS adopts a number of lightweight body components in line with the approach taken for the M4 CS. These include a carbonfibre-reinforced plastic roof and bonnet. The new roof is claimed to save 6kg over the steel structure in the standard M3.
Further lightweight components include a carbonfibre front splitter, a lift-reducing boot-deck-mounted Gurney spoiler and a sizeable diffuser.
Inside, the M3 CS acquires the lightweight M sport seats and sport steering wheel from the M3 Competition Package. Borrowing a cue from the new M5, there’s also a new red starter button.
Despite the focus on performance, features such as BMW’s Professional navigation system, climate control air conditioning and a Harman Kardon sound system are fitted as standard, and the rear seats are retained. However, buyers can specify the new four-door with a series of unique Alcantara and leather accents as an option.
Overall, BMW M claims a 10kg reduction over the standard M3 at 1585kg. Although this is not a significant loss, insiders suggest the M3 CS’s centre of gravity is lower than that of the already heavily focused M3 Competition Package.