• Audi produces factory-upgraded high-performance RS models of certain versions of their normal cars. RS stands for the German RennSport, which translates to "racing sport," and it is the highest trim level available. The first RS, the RS2 Avant, was released from 1994 to 1995. Since then, RS models have been released sporadically.
  
  

RS2 Avant

• Designed by Audi and Porsche, the 1994 RS2 Avant is a five-door compact executive sports car with a 2.2-liter, five-cylinder, 20-valve turbo engine and a six-speed manual transmission. The engine produces 315 horsepower and 302 ft.-lbs. of torque. It measures 177.6 inches long, 66.7 inches wide and 54.6 inches high.
  
  

RS4 Avant

• The 2000 Audi RS4 Avant sports a 2.7-liter V-6 engine that produces 375 horsepower and 324 ft.-lbs. of torque. This car measures 178.1 inches long, 70.8 inches wide and 54.6 inches tall.
  
  

RS6 Quattro

• The 2003 RS6 Quattro sports a 4.2-liter V-8 engine that produces 450 horsepower and 415 ft.-lbs. of torque. With a bore of 3.32 inches and a stroke of 3.66 inches, it has a compression ratio of 9.8 to 1. This engine has a turbocharger and a 40-valve double overhead camshaft. This four-door sedan measures 191.3 inches long, 78.4 inches wide and 56.1 inches high.
  
  

RS4 Quattro

• The 2008 Audi RS4 Quattro's 4.2-liter V-8 engine produces 420 horsepower and 317 ft.-lb. of torque. Its 3.33-inch bore and a 3.65-inch stroke yield a 12.5 to 1 compression ratio. With four doors, this sedan measures 180.7 inches long, 71.5 inches wide and 55.7 inches tall.