The BMW Z4 3.0si 265hp (E85 - 2003 - 2008) produces 265bhp and 315Nm in standard form. Our Stage 1 ECU tuning file raises output to 280bhp and 360Nm, a gain of 15bhp and 45Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.