The Dodge Viper 8.4 V10 640hp (2008 ->) produces 640bhp and 815Nm in standard form. Our Stage 1 ECU tuning file raises output to 670bhp and 875Nm, a gain of 30bhp and 60Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.