The Audi S4 4.2 Liter is an exceptional car, featuring a superb chassis and Audi’s renowned quattro technology. However, there's always been room for improvement in the power department. Our engineers set out to elevate the car’s performance by integrating a water-cooled, roots-type Eaton TVS1900 supercharger. Tuned to produce 5.5 psi, this supercharger is designed to deliver exhilarating torque and significantly increased horsepower.