The Mercedes GLK 250 CDI 204hp (X204 - 2010 ->) produces 204bhp and 500Nm in standard form. Our Stage 1 ECU tuning file raises output to 240bhp and 580Nm, a gain of 36bhp and 80Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.