German tuner Performmaster has lifted the wraps off its newest Mercedes-AMG-based product: an uprated version of Affalterbach's flagship GT 4-Door Coupé. 

Limited to just 31 units, the saloon's twin-turbo 4,0-litre V8 engine has been equipped with the firm's "PEC" tuning module. Thanks to this electronic modification, the AMG mill now produces a staggering 544 kW and 1 030 N.m of torque. Power is sent to all four corners via a nine-speed automatic transmission, replete with a wet clutch and a launch control function.

Not only does it offer 74 kW and 130 N.m more than the standard GT63 S (which Mercedes claims is “fastest fully fledged four-seater production car” round the Nürburgring), it's also more powerful than any car currently on offer from the Mercedes-AMG stable. 

The Plüderhause-based company claims the two-tonne family coupé is now capable of completing the 0-100 km/h sprint in a mere 2,9 seconds (0,3 seconds quicker than the standard car). The 314 km/h top speed has, however, remained.

Exterior upgrades are subtle, with the most notable addition being the "Aersphere" rear wing, which extends at speed. Other items include a revised front splitter, which the company calls a "front sword" (presumably because it's designed to cut through the air), and a rear diffuser. Compared with the standard version, this tuned limited-edition model's suspension has been lowered for improved driving dynamics. 

Pricing for this modified super saloon is not yet known, but it'll obviously fetch quite a premium over standard car's (local) price tag...