The Cadillac XLR 4.6 V8 326hp (2006 - 2009) produces 326bhp and 423Nm in standard form. Our Stage 1 ECU tuning file raises output to 346bhp and 450Nm, 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.