Previous Audi S4s have had twin-turbocharged V6s and naturally aspirated V8s underhood. But Audi wants to be known for innovation, so this S4 is outfitted with a supercharged V6. The direct-injected, 333 horsepower 3.0-liter V6 in the 2010 S4 may just be the best engine an S4 has ever seen. It’s 11 horsepower shy of the previous V8’s 344 hp, but it makes 325 lb-ft of torque (23 lb-ft more than the V8).
You can have that supercharged V6 with a 6-speed manual transmission or a new 7-speed dual-clutch transmission, which features steering-wheel-mounted paddle shifters. Ticking the dual clutch option gets you substantially faster shifts, and because of the additional gear ratio, quicker acceleration. Seven speeds equal better miles per gallon, too. With the dual-clutch transmission, the new S4 is actually 27 percent more fuel-efficient than the previous car. Audi estimates around 16/28 mpg (city/hwy).
As always, the S4 is available only with Audi’s quattro all-wheel drive system. This year, the S4 sports a revised 40:60 front/rear torque split to help accentuate the car’s sporting character, as well as what Audi is calling a sport differential. The system uses clutch packs to change the amount of torque delivered to each of the rear wheels, which serves to eradicate understeer by forcing power to the outer wheel. The system can send as much as 100 percent of torque (per axle) to the outside wheel, making turn-in much more apparent than many existing systems.
Source: MSN Autos