With 435 HP and 400 pound-feet (542 Nm) of torque, the stock Ford Mustang GT is anything but slow.

However, GeigerCar’s idea of how the muscle car should feel like includes almost 400 HP more, up to a total of 820 HP and 560 lb-ft (759 Nm) of torque, which will significantly improve performance, although the tuner hasn’t announce any zero to sixty or new top speed numbers.

In order to squeeze the extra oomph from the 5.0-liter V8 engine, the Germans have added a 2.9-liter supercharger, forged pistons, steel connecting rods, fine-balanced crankshaft, stainless steel sports exhaust system and a cold air intake.

Improve handling is the new sport tuned suspension and the GT Performance package, which adds a Torsen limited-slip rear differential, Brembo B6-piston brakes and a 3:73:1 final drive ratio.

Besides the changes performed underneath its skin, GeigerCar’s Mustang GT has also received a carbon fiber body kit, which includes a front splitter, open grille, different side skirts, trunk-mounted spoiler and rear diffuser. The muscle car rides on 20-inch lightweight forged alloy wheels, which have been wrapped in high-performance Michelin 255/35 front and 295/30 rear rubber.

The tuner’s upgrade package for the muscle car costs 109,450 ($124,285), but customers can also purchase some of the components individually.

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