The BMW 6 Series 645ci 333hp (E63 - 2004 - 2010) produces 333bhp and 450Nm in standard form. Our Stage 1 ECU tuning file raises output to 355bhp and 480Nm, a gain of 22bhp and 30Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.