The Mercedes GLK 250 CGi 211hp (X204 - 2010 ->) produces 211bhp and 350Nm in standard form. Our Stage 1 ECU tuning file raises output to 230bhp and 420Nm, a gain of 19bhp and 70Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.