Photos: Audi S cars at the Paris Motor Show

That's not just an S-line trim package on an A3; this car is the real deal, the European S3. As such, it's lower to the ground than the standard A3 and features a stiffer suspension. Audi's Quattro all-wheel-drive is standard.

The S3 gets all of Audi's cabin tech, including navigation and iPod integration. The sport flat-bottom steering wheel is standard. Transmission choices include a six-speed manual or Audi's double clutch S-Tronic six-speed gearbox.

Although the U.S. A3 and the S3 shown at the Paris Motor Show share similar engine configurations, both being turbocharged 2-liter four cylinders, Audi squeezes more power from the S3's engine through the use of a larger turbo and other engine refinements. The S3 produces 265 horsepower where the A3 does 200 horsepower. The S3 with the S-Tronic transmission gets to 62 mph in 5.5 seconds.

The S4 will be sold in the U.S. This new model shown at the Paris Motor Show follows on the launch of the new A4 last year. Both the new A4 and S4 use Audi's new styling cue of LED parking lights. The S4 has Audi's Quattro all-wheel-drive system, along with a newly designed rear differential that actively pushes torque to the outside wheel in a turn, helping the car pivot around corners.

Where the previous S4 model used a V-8, Audi puts a V-6 in the new S4. However, this smaller engine uses a supercharger to produce similar power, 333 horses and 325 pound-feet of torque, getting the S4 to 62 mph in just 5.1 seconds.

Audi fits the S4 with a new seven-speed dual-clutch S-Tronic transmission. Similar to the seven-speed DCT found in the BMW M3, this S-Tronic has a fuel-saving automatic mode, or can let the driver make lightning-fast shifts with paddles.

At the level of scary is the RS6, first seen in sedan guise at the Paris Motor Show. An Avant, or wagon, version was shown last year. RS is a step above S in Audi tuning, so you know the RS6 is going to be an impressive car. Audi claims it's the more powerful production sedan in the world.

The RS6 uses a twin-turbo V-10 engine the puts out an astounding 580 horsepower and 480 pound-feet of torque. That means just 4.5 seconds from 0 to 62 mph. The top speed is governed at 155 mph, but Audi will reset that to 180 mph on request.

The RS6 stays stable in the turns through the use of an adaptive suspension, which uses hydraulics to counteract roll. Less impressive is the six-speed automatic transmission, although Audi claims to refined it for fast sport shifting.

As the RS6 is based on the A6, the cabin gets the executive treatment, with navigation, Bluetooth cell phone integration, and a high-end audio system.