The Porsche 911 was available in seven variations for 2003. The base 911s were the Carrera coupe and cabriolet (or convertible), which were powered by a 3.6-liter flat, or horizontally opposed, six-cylinder engine that produced 315 horsepower. Like in all 911s, the water-cooled engine was mounted in the rear and provided power to the rear wheels. The base 315-horsepower, six-cylinder engine also powered the Carrera 4 cabriolet, the Carrera 4S, and the 911 Targa models. Stepping up a notch, as far as power was concerned, the 911 Turbo was equipped with a twin-turbocharged 3.6-liter horizontally opposed six-cylinder engine that produced 415 horsepower. And at the high end of power range was the 911 GT2, which drew on Porsche's racing heritage with a lighter, more responsive body and a 3.6-liter six-cylinder with an engine management system that boosted horsepower to 456. A six-speed manual overdrive tranmission was standard for all 911 models, while a five-speed automatic Triptronic transmission, with a gate and steering-wheel-mounted controls for manual shifting, was available as an option. Porsche added an in-dash CD player to the 911's standard AM/FM audio system for 2004. Other standard features for the 911 were extensive, as befitting an exotic sports car, and included air conditioning, leather seats, dual front and side airbags, a keyless entry system, cruise control, a trip computer, power heated mirrors, a leather-wrapped steering wheel, an anti-theft alarm system, a power-adjustable driver's seat, power heated mirrors, and a leather-wrapped steering wheel, as well as powered windows, steering, brakes, and door locks. Four-wheel anti-lock brakes and a rear spoiler were also part of the package. The hard-top models added a power sunroof, while the Turbo added traction control and the Carrera 4S added stability control. The 2003 Porsche 911 was one of a long line of near iconic Porsche sports cars that promised a lot to drivers, and delivered on those promises in almost every way. Drivers noted that the car's power, handling, precise steering, braking, suspension, and interior all met or exceeded expectations. Drivers also noted that visibility out the rear was exceptional, as was reliability, though some drivers noted that the back seat in the 2+2 models was cramped.