In stock form, the Bavarian roadster sports the E39 M5's 5.0-liter V8 engine delivers 400-horses and a peak torque of 500Nm(368.8 lb-ft).
After the addition of a sports filter, a custom exhaust system and a light ECU tune, output is lifted to 450-horses and 535Nm (394.6 lb-ft) with Senner stating that the modded Z8's top speed is in excess of 300km/h (186mph)[...]