The Mercedes E 420 CDI 314hp (W211 - 2002 - 2006) produces 314bhp and 730Nm in standard form. Our Stage 1 ECU tuning file raises output to 354bhp and 810Nm, a gain of 40bhp and 80Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.