The Chevrolet Express 4.8 V8 275hp (2001 - 2007) produces 275bhp and 393Nm in standard form. Our Stage 1 ECU tuning file raises output to 295bhp and 420Nm, a gain of 20bhp and 27Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.