The important details to justify the CSL tag are as follows. What started out as a regular M2 Competition has seen various weight-saving measures reduce overall weight by around 242 lbs - placing it in a similar ballpark to the curb weight of the E46 M3 CSL. Then, the twin-turbocharged S55 inline-six under the hood got some massaging from Beek Auto Racing in the Netherlands while the exhaust was swapped out for a full system from Akrapovic. The result: 520 horsepower and 487 lb-ft of torque.
This is routed rearwards by the standard seven-speed DCT, but it has a custom software tune from Defined Coding in the UK, which also worked its magic on the rear differential to improve handling and power deployment. The front brakes were beefed up with a 380-mm, six-pot front set from Nashin in Japan, while suspension components arrived courtesy of AST Suspension.