The Mercedes-Benz specialists at Renntech have turned their expertise to the S63 AMG Coupe and created a menacing luxury vehicle with a dyno-verified 588 horsepower at the wheels. The matte black paint, dark emblems, and the firm’s prototype decklid spoiler combine to give the big two-door the look of a stealth jet ready for takeoff.

In stock form, the S63 AMG Coupe's 5.5-liter biturbo V8 makes an already plentiful 577 horsepower and 664 pound-feet of torque. Renntech then adds an ECU upgrade that  takes the output to a claimed 669 hp and 734 lb-ft. The tuner’s downpipes with 200-cell catalytic converters add another 10 hp and 15 lb-ft. After installing sport mufflers with electronic valves and tuning all the parts to work together, Renntech reports its S63 makes 708 hp and 839 lb-ft at the crank.

The company’s numbers are nothing without verification, though, and Renntech has the dyno figures to back up its claims. A stock S63 AMG Coupe made 445 hp and 489 lb-ft at the wheels. After the tuners installed their parts, the stats jumped significantly to 588 hp and 697 lb-ft.

Getting so much additional power out of the S63 AMG Coupe isn’t cheap, though. Assuming you already paid the $164,075 base price for the Mercedes, Renntech’s upgraded ECU alone costs $3,495. The improved downpipe and catalytic converters are $4,940 more. If you have that much cash to spend, paint your coupe matte black like this one for some extra style to go with the additional speed.

Source: Renntech

Gallery: Mercedes-Benz S63 AMG Coupe by Renntech