While the 3.0 TFSI is less powerful than the naturally aspirated 344 HP 4.2-liter V8 engine on the outgoing S4, the supercharger offers the V6 unit a higher torque output with power spread more evenly across the torque curve. In particular, the 3.0 TFSI delivers a maximum torque of 440 Nm (324.53 lb-ft) at 2,500 rpm and maintains this constantly until 4,850 rpm (previous S4: 410 Nm at 3,500 rpm). Power is transferred to the road via a six-speed manual gearbox or optionally, through Audi’s S-Tronic seven-speed dual clutch semi-auto transmission.
As with all sporty Audis, the S4 is equipped with the latest generation quattro permanent all-wheel-drive system that sends 40 percent of its torque to the front wheels and 60 percent to the rear. Where necessary, it can vary distribution within fractions of a second. The S4 also gets Audi’s new active sport differential that complements the quattro drive system.
In terms of performance, the new Audi S4 Sedan sprints from 0 to 100 km/h (62mph) in just 5.1 sec undercutting its predecessor by half a second. In fourth gear, the vehicle accelerates from 80 to 120 km/h (49.71 to 74.56 mph) in 4.4 seconds. Like the previous S4, top speed is electronically limited to 250 km/h or 155 mph.
Equally important, the new 3.0 TFSI is more fuel efficient than the 4.2-liter V8 consuming on average, 9.7 liters of fuel per 100 km (24.3
As for appearance, both the S4 Sedan and the S4 Avant get a few minor exterior modifications that include the special aprons, the chromed grille, the aluminum-look exterior mirrors, the 18-inch S-design light-alloy wheels, the side rocker panels, the restrained spoiler at the rear and the quadruple exhaust system. Inside the S4s feature a set of sport seats up front while the instrument panel features gray dials with white needles. Audi will begin delivery of its new S4 models in March 2009.