Based on the 220-horsepower A4 sedan, the S4 ratchets up the performance quotient with a 333 horsepower, 325 lb-ft of torque 3.0-liter V6 engine that yields a zero-to-60 mpg time of five seconds and an electronically limited top speed of 155 miles per hour. A six-speed manual comes standard, while a seven-speed dual-clutch automatic is also available. Fuel economy is rated at 17/26 with the manual and 18/28 with the automatic.
Complementing the upgraded powertrain is a tightened and lowered suspension that helps the S4 hug the curves like a sports sedan should.
The S4 is distinguishable from its less potent kin by a more aggressive front fascia with more foglamp housings and a metallic-trimmed grille. From the side, one will notice more sporty wheels, mounted outside larger, high-performance calipers and rotors that help bring the performance-minded car to a halt. Continuing to the rear, the S4 features a unique rear fascia and badging that will let more pedestrian vehicles know exactly why they are viewing the back - and not the front - of the S4.
Inside, S4-specific touches include black and gray contrasting leather accents along with S-line gauges, door sills and badging. Otherwise, the interior is essentially the same as that of the standard A4, with a modern-looking dash, plenty of high-quality materials and a relatively spacious backseat for the segment.
The S4 is available with Audi's MMI infotainment interface and Audi Connect, which brings in-car internet connectivity and industry-first Google Earth integration - complete with panoramic views and high-resolution 3D satellite and aerial imagery.
Standard and Optional Features
The S4 can be had in two trim levels - Premium and Premium Plus.
The Premium models comes standard with Nappa leather upholstery, heated front seats, a 10-speaker AM/FM/CD/SiriusXM stereo system with iPod integration, Bluetooth connectivity, tri-zone automatic climate control, 18-inch alloy wheels, foglights, xenon headlights and LED taillights.
The Premium Plus trim adds a navigation system with Audi Connect a 12-speaker, 505-watt Bang & Olufsen sound system with HD ratio technology, Audi side assist and a rear parking Camera.
Notable options include ventilated seats, adaptive cruise control and a performance-oriented Sport Differential package with torque vectoring. Also available is Audi Drive Select, which offers a variety of different suspension, steering, transmission and engine calibrations.
The Premium Plus model can also be optioned with Audi side assist, which monitors the blind spot areas, as well as fast-approaching vehicles.
The new Black Optic appearance package includes 19-inch 5-V-spoke design Titanium-finished wheels.
All S4 models are fitted with dual front, side thorax and side curtain airbags along with stability and traction control systems and electronic brake-force distribution with brake assist. Rear side airbags are available as an option.
The S4 is aimed at the competition's mid-grade small sedans that slot between the base-engine cars and the performance models. These include the Mercedes-Benz C450 AMG Sport and the BMW 340i.