American RENNtech tuning studio presented its four-door coupe version of the Mercedes-Benz CLS63 AMG. No external update the car does not turn out – all the forces of the company’s specialists have focused on improving its dynamic performance. As stated in the company presented a package is the first stage of improvements prepared. While the kit includes only the new ECU and sport exhaust system. Such an innovation would raise output and maximum torque of CLS63 AMG with a base 557 hp and 800 Nm to 669 hp and 995 Nm, respectively. Acceleration from zero to hundreds fell from 4.3 to 3.4 seconds. At the International Circuit in Palm Beach, CLS63 AMG is the tuning of the RENNtech was faster than Nissan GT-R in the race for a quarter mile, showing the speed at the finish line in the 201 km/h. Cost of the improvements is 3495 dollars.