The Audi A6 S6 4.0 TFSI 450hp (C7 - 2011 - 2018) produces 450bhp and 550Nm in standard form. Our Stage 1 ECU tuning file raises output to 540bhp and 800Nm, a gain of 90bhp and 250Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.