The car world is lousy with fly-by-night tuning shops. RENNtech isn't one of them. Founded in the 1980s by 15-year AMG veteran Hartmut Feyhl, the Florida shop has put the screws to hundreds of Mercedes-Benz (as well as Porsche and BMW) products over the decades.


Renntech's tuning work ranges from simple software upgrades to full racing builds, and its shop is a tropical wunderland for anyone fascinated with how digital technologies and mechanical bits can intersect to achieve UÜBER POTENTIAL.

In this episode of Tuned, Matt Farah takes a 700 horsepower CLS63 for a spin, and tries to establish a new benchmark for luxury sedans: the ability to do burnouts at highway speeds.