Mercedes-Benz made a big splash with the introduction of its CLK63 AMG Black Series coupe last year. The aggressive "F1 safety-car" look gave the 500 hp CLK Black a visual edge that the CLK55 AMG lacked, and the Black Series' suspension and brakes were in a decidedly different league compared to other Mercedes.
Impressive spec sheet notwithstanding, some customers will still believe that 500 hp is not enough, and for those select few who find the CLK a bit tame, there is always RENNTECH.
Established in 1989 by Hartmut Feyhl (ex technical director: AMG North America), RENNTECH quickly made a name for itself with high-powered magazine tuner-shootout cars that were reliable enough to actually be driven from RENNTECH's home in South Florida thousands of miles to events in Texas and Michigan. For the CLK Black, Feyhl told his crew to develop the same kind of "real-world" performance upgrades that made his cars so famous to begin with.
"Real-world performance is all about torque, not so much about a peak horsepower number at very high rpm," explains Feyhl. "It can be very easy to build high rpm horsepower, but to get instant throttle response and mid-range acceleration it is more difficult, and this is where customers really want to feel that improvement." To build that improvement, RENNTECH adds long-tube headers and a motorsports style exhaust to the already-potent 6.2 liter engine, tying it all together with RENNTECH's own ECU software, sharpening throttle response and boosting 550 peak hp. The real story, however, is drivability - and this is where the RENNTECH tuning package shines, delivering an additional 45-60 lb-ft of torque between 2400 and 5000 rpm.
To "sharpen" the car even further, RENNTECH fine-tuned the CLK63 Black Series' suspension, lowering the car 3/4" and adding carbon-fiber strut braces front and rear. To enhance mechanical grip in fast corners, RENNTECH also added fully-adjustable camber bushings at all four corners. Aerodynamic stability is also greatly enhanced with an adjustable carbon-fiber rear wing element and a front splitter/rear diffuser combination to manage underbody airflow, building usable downforce and (adjustable) aerodynamic balance at speed, while directing cooling air to the Black Series' huge AMG brake rotors - themselves enhanced with high-performance pads and stainless-steel braided lines. The result is a hard-core CLK63 from RENNTECH that does the unthinkable: it makes the standard CLK63 seem a bit soft.
Contact RENNTECH for more. CLICK HERE for more pics.
