Progressively more stringent emissions and noise regulations, environmental concerns, a higher expectation for refinement and the need for a high-performance 4 valve per cylinder engine made the switch necessary.

Other major changes include a completely new platform having a sleeker body with a more raked windshield, and a re-designed interior along with new "fried egg" shaped headlamps (so called due to the amber coloured turn signals) instead of previous "bug eye" headlamps.

[3][citation needed] During the 1990s, Porsche was facing financial troubles and rumours of a proposed takeover were being spread.

[6] In 2000, Porsche introduced the 996 Turbo, equipped with a four-wheel-drive system and a 3.6-litre, twin-turbocharged and intercooled flat-six engine generating a maximum power output of 309 kW (420 PS; 414 hp),[7] making the car capable of accelerating from 0–97 km/h (0–60 mph) in 4.2 seconds.

An X50 option which included larger turbochargers and intercoolers along with revised engine control software became available from the factory in 2002, increasing power output to 331 kW (450 PS; 444 hp).

2002 also marked the start of the production of the 996 based Targa model, with a sliding glass "green house" roof system as introduced on its predecessor.

The Turbo is powered by a water-cooled twin-turbocharged and intercooled 3.6-litre flat-6 engine derived from the 1998 Le Mans winning 911 GT1 race car.

It has revised styling and a wider stance than the naturally aspirated 996 Carrera models, along with new bi-xenon headlamps and a retractable rear wing.

In 2002, the X50 package was offered as an option on the Turbo that included larger K24 turbochargers and intercoolers, a revised ECU and quad-pipe exhaust which raised power output to 331 kW (450 PS; 444 hp).

[7] Other features introduced in 2002 were a glove box, center mounted cup-holders, an optional Bose stereo and rain-sensing wipers.

The GT3 was based on the standard 996 Carrera, but was stripped of a great deal of equipment for weight savings, featuring stiffer, adjustable suspension and upgraded brakes.

It featured a naturally aspirated 3.6-litre flat-six engine generating a maximum power output of 265 kW (360 PS; 355 hp).

[17] The Mk.II GT3 variant was based on the second generation of the 996, and featured updated aerodynamics, and a more powerful version of the 3.6 L engine from the MK.I, now rated at 280 kW (381 PS; 375 hp).

[19] The turbocharged counterpart to the GT3, the GT2, was rear-wheel drive as well, to save weight and to avoid power losses through the transmission[20] (This is primarily due to the fact that the GT2 was built to compete in GT2 class racing, which restricted the use of an all-wheel-drive system).

[20] The GT2's fixed rear wing (made of CFRP for the post-2003 cars) appears to be a concession to racing rules that usually outlaw adjustable aerodynamic components.

This special edition was finished in Violet Chromaflair paint with natural leather interior and dark burr maple trim.

A number plate on the center console and a unique "911" badge on the engine lid and lettering on the door sills make this special edition easy to identify from other base Carrera models.

Other unique features included: X51 power kit, turbo radiators, limited slip differential, sport suspension, polished 5-spoke alloy wheels (unique to this model), GT3 side skirts, natural gray leather interior (with matching luggage set), sports seats (there was a power comfort seat option), polished exhaust tips, heated seats (option in Latin America), litronic bi-xenon headlights, special dynamic sealed panels, and a special "40 Jahre 911" logo on the engine cover.

The rear main seal issue in some models was due to improper machining, requiring engine replacement to correct for chronic RMS leaks.

[25] Specifications for the MkI, EU spec 996 models: Specifications for the MkII, EU spec 996 models: Production Numbers:[27] Hollywood custom car builder Eddie Paul created a modified 996 Carrera as one of a set of three vehicles for Pixar's 2006 Cars promotional tour.

[28] Sally, a blue Porsche 996 designed to closely resemble a 2002 Carrera, is built on a slightly shortened wheelbase; her windshield is tilted closer to vertical (adding a few inches to the car's height) to accommodate the animated character's eyes.