Brabus’ Mercedes S500-based PowerXtra B50 Hybrid is a gasoline-electric rocket

Brabus, one of Germany’s best-known tuners, has unveiled the PowerXtra B50 Hybrid, a more extreme version of Mercedes’ politically-correct S500 plug-in hybrid sedan. The B50 immediately stands out from the S500 thanks to a comprehensive list of upgrades in the engine bay.

The gas-electric sedan benefits from a re-mapped ECU that modifies the fuel injection and ignition settings, and it gains a tweaked turbocharger that provides a lot more boost. As a result, the 500’s 3.0-liter V6 engine makes 385 horsepower at 5,600 rpm and 405 foot-pounds of torque over a wide band that stretches from 1,600 to 4,000 rpm.

The system’s total output rises to 500 horsepower and 656 foot-pounds of torque, allowing the 4,700-pound B50 to reach 62 mph from a stop in 4.9 seconds – 0.3 seconds faster than a stock S500 – and go on to a top speed that’s electronically limited to 155 mph. Brabus has not revealed what effect the power bump has on gas mileage.

The B50 uses the same seven-speed automatic transmission as the S500, and the four driving modes (called Hybrid, E-mode, E-save and Charge, respectively) have been carried over with no modifications. S500 owners looking to get the full Brabus treatment can order a custom-designed stainless steel exhaust system with four tail pipes at extra cost.

Brabus has designed an aerodynamic body kit specifically for the S500. The B50’s front end benefits from a redesigned front bumper that incorporates three large air vents and a discreet Brabus-badged splitter, while the rear fascia gains a trunk-mounted spoiler and an air diffuser . Side skirts, fender vents made of carbon fiber and 20-inch alloy wheels wrapped by Continental tires add a finishing touch to the look.

Far from a simple design study, the Brabus PowerXtra B50 Hybrid is on sale now in Germany.  The tuner has not published pricing information, and it has not revealed if the super-hybrid will be available in other countries.