The Audi S8 4.0 TFSI 571hp (2019 ->) produces 571bhp and 800Nm in standard form. Our Stage 1 ECU tuning file raises output to 600bhp and 900Nm, a gain of 29bhp and 100Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.