German tuning shop Dähler is giving a significant power upgrade to the BMW M850i xDrive Convertible. With their Stage 1 kit, the M850i powered by the 4.4-liter twin-turbo V8 now makes 627 HP and 850 Nm … Continue reading BMW 8 Series Convertible: Dähler-Tuning brings the M850i ​​to 627 hp