The staple of advanced or professional driving is the "rev match", or "throttle blip", in which the driver quickly brings the engine up to speed with the wheels by use of the throttle. This was not possible with the automatic transmission in the CLK Black Series…until now.

RENNtech is proud to offer our Speedshift performance valve body upgrade for the CLK black series. Our upgrade modifies the shifting performance characteristics of the transmission control unit, the transmission valve body and allows the vehicle to automatically “blip” the accelerator upon down shifts allowing for quicker gear engagement and faster lap times.

When downshifting, the engine throttle is increased to allow the engine to match the RPM of the lower gear and allows for significantly faster gear engagement . When coupled with our transmission upgrade, this is the ultimate upgrade for your CLK Black series.

**VIN NOTE** RENNtech often requires your vehicle's VIN number to process orders. Please leave this information in a note during checkout or email us with your order number after order is placed*

RENNtech has become the premier Mercedes-Benz specialist and Hartmut Feyhl himself is regarded by many as USA’s foremost authority in Mercedes tuning. His vast experience comes from 12 years spent at AMG Germany before serving as the North American division’s Technical Director. Prior to the tuning company’s merger with Mercedes-Benz in 1999, by the request of AMG Germany, Feyhl branched out on his own to start RENNtech and service the existing AMG North America customers.

Performance without compromise. This is the foundation upon which we have built our reputation. Established in 1989 by Hartmut Feyhl, RENNtech has evolved and grown from servicing AMG’s customers into the foremost authority on tuning and customizing AMGs and Mercedes-Benz. RENNtech also offers tuning solutions for Porsche, Audi and Bentley vehicles, along with other European luxury cars.

Over the years, we have developed high-performance products for virtually all Mercedes-Benz AMG vehicles. Some of the most notable among these are the 200 mph RENNtech E7.4RS (which claimed ‘Fastest Sedan in the World’ honors by Car and Driver Magazine in 1996) and the more recent 945 LB-FT 5.5L V8 Biturbo RENNtech R3+ Monster. Each of these vehicles are just a sampling of what RENNtech has achieved, featuring extreme performance, upgraded aesthetics and a fit and finish that rivals factory vehicles.

We design, engineer and manufacture our proprietary line of tuning products in-house at our facility which features a full fabrication and machine shop with CNC and rapid prototyping capabilities; in-house performance dynos, complete engine management and software tuning capabilities along with a complete service/repair/installation facility and a full-time design, engineering and sales staff.

Our headquarter facility is located just north of the Palm Beaches in Stuart, Florida