The BMW 5 Series M 550D - 381hp (F10/11 - 2010 - 2016) produces 381bhp and 740Nm in standard form. Our Stage 1 ECU tuning file raises output to 420bhp and 800Nm, a gain of 39bhp and 60Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.