Starting from the twin-turbocharged 5.5-liter V8 in the “regular” CLS 63 AMG model, Brabus engineers increased the cylinder displacement to 5.9 liters, while also replacing the turbocharger compressors with slightly larger ones.
Not thinking that would be enough, they also replaced the intake system with one that uses gold-plating for an improved temperature efficiency, a more free-breathing exhaust system that sounds like an angry Norse god and an all-new ECU to control all of the above.
The result is very much on the “Holy mackerel!” side, with the “standard” 557 hp and 720 Nm (531 lb ft) of torque becoming no less than 850 hp and a massive 1450 Nm (1069 lb ft) of torque.
Naturally, since that unholy amount of torque would probably cook the transmission along with the rest of the drivetrain at any given time, Brabus opted to electronically-limit the maximum torque to “just” 1150 Nm (848 lb ft). With 4Matic all-wheel drive, those numbers are still enough to keep the back of your head firmly-pressed against the headrest everytime you launch the car from a dig.
To put things into perspective, the naught to 100 km/h (62 mph) acceleration time of this black beast sits at just 3.1 seconds, making it as fast as the Porsche 911 Turbo S (991). Impressive, and the adjacent photos of the animal aren't half bad either.