The Citroen C4 1.6 VTi 120hp (2004 - 2010) produces 120bhp and 160Nm in standard form. Our Stage 1 ECU tuning file raises output to 130bhp and 180Nm, a gain of 10bhp and 20Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.