Mercedes-Benz S63 AMG Coupe taken to 708 hp by Renntech image

The German aftermarket specialists from Renntech have decided the Mercedes S63 AMG Coupe needs a serious power bump and as a result even on the dyno the luxo-coupe brings almost 600 horsepower at the wheels.

To support the power credentials, the visual enhancements include a menacing matte black paint, dark emblems, and the firm’s prototype decklid spoiler. Now looking like a stealth jet ready for take-off, the S63 AMG Coupe also presents the output modifications, Its standard 5.5-liter biturbo V8 comes up the factory gates with 577 horsepower and 664 pound-feet of torque but Renntech turned to an ECU upgrade for a power of 669 hp and 734 lb-ft. The tuner didn’t stop there and added downpipes with 200-cell catalytic converters for another 10 hp and 15 lb-ft. Following the installation of sport mufflers with electronic valves and tuning all the parts to seamlessly blend together, the S63 makes 708 hp and 839 lb-ft at the crank.

Mercedes-Benz S63 AMG Coupe taken to 708 hp by Renntech 4

The company has decided to also hit the dyno to support its claims, presenting the findings. A regular S63 AMG Coupe has 445 hp and 489 lb-ft at the wheels – and following the rework the Renntech build comes up with 588 hp and 697 lb-ft. These modifications don’t come cheap though. The base S63 AMG Coupe is $164,075, you have to add $3,495 and $4,940 just for the ECU update and improved downpipe and catalytic converters.