The BMW 5 Series 550i Valvetronic 449hp (F10/11 - 2010 - 2016) produces 449bhp and 650Nm in standard form. Our Stage 1 ECU tuning file raises output to 540bhp and 780Nm, a gain of 91bhp and 130Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.