The CLK 63 Black Series was a significant departure when it arrived. Mercedes-Benz’s reputation for engineering brilliance has been well-established for over a century, but it's usually used for safety, refinement, and luxury. With some regularity, that brilliance is also used to strap a rocket motor to the safe, refined, and luxurious Mercedes passenger cars.
Every so often, however, the might of Mercedes engineering is unleashed to make a car that is not just fast, but also genuinely athletic. The CLK 63 Black Series did that in a way that is rare for a Mercedes. In addition to having a boatload of power, the Black Series gained a whole host of weapons-grade improvements that made it clear that its mission was complete performance. Upgrades included triple adjustable coilovers, a significantly widened track with the bodywork to go with, a strengthened body shell, massive brakes, deleted back seats, and a limited slip, and even a differential cooler.
The car marked one of the first appearances of the M156, the first and so far only engine designed by AMG, rather than merely tuned and assembled by them. Its 6.2 naturally-aspirated liters, quad cams, four valves per cylinder, variable valve timing and intake runner length make it an all-time great internal combustion engine; it has power and torque everywhere and revs to 7,200 RPM.
This power is transmitted, regrettably, through a 7-speed automatic transmission, which was the biggest source of criticism in the entire car from those who reviewed it in period. The transmission is perfectly fine in regular driving, but when pressing on, it prevents the driver from having full authority over the glorious engine and that’s really a shame.
To address that concern, this car was converted to a manual transmission in 2024-2025 by Kwiek Classics, based in Nashville Tennessee. The third such car converted by them, it uses entirely Mercedes components with the exception of the clutch. The transmission, flywheel, shifter, pedal cluster, hydraulic components (even the pre-formed hydraulic lines) are all Mercedes-Benz parts.
The experience feels high quality and impressively natural, as though the car left the factory configured this way. The engine response is excellent, the gearchange precise and mechanical, and the clutch action progressive. The overall experience is transformed by the ability to interact directly with the engine.
Prior to its swap, the car was well maintained, receiving the updated SLS Black Series valve bucket set to address one of the common M156 weak points. Other recent maintenance in the 2024 included an oil change, new battery, resealed differential, and new motor mounts. In addition to the manual transmission swap, this car also has Girodisc brake rotors and pads.
Included with the car is a binder of service records and the original owner’s manual pack.
