The Jeep Grand Cherokee 4.7 V8 305hp (2005 - 2011) produces 305bhp and 453Nm in standard form. Our Stage 1 ECU tuning file raises output to 325bhp and 475Nm, 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.