G-Power is one of them.
BMW tuning expert G-Power has pushed the boundaries once more, unveiling the “ultimate M5” it calls the G5M Bi-Turbo. In stock form, the BMW M5 is one of the most powerful sedans on the planet, its 4.4-liter twin-turbo V8 delivering 560 hp and 501 lb-ft of torque. G-Power has managed to increase output to 740 hp and 719 lb-ft of torque. Its previous project, the M5 Hurricane, was rated at 820 hp and capable of hitting a 220 mph top speed.
By describing this M5 as “the ultimate” we have to assume it can better that top speed and deliver a 0-62 mph time of around four seconds. As always, exterior mods are limited, and appear to extend to a new set of 21-inch forged alloys wrapped in Michelin Super Sport tires.