The BMW 5 Series 520D 136hp (E39 - 1995 - 2003) produces 136bhp and 280Nm in standard form. Our Stage 1 ECU tuning file raises output to 168bhp and 348Nm, a gain of 32bhp and 68Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.