The BMW 5 Series 520i 170hp (E60/61 - 2003 - 2010) produces 170bhp and 210Nm in standard form. Our Stage 1 ECU tuning file raises output to 182bhp and 230Nm, a gain of 12bhp and 20Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.