The Isuzu Ascender 4.2 275hp (2003 - 2008) produces 275bhp and 373Nm in standard form. Our Stage 1 ECU tuning file raises output to 295bhp and 395Nm, a gain of 20bhp and 22Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.