Porsche 911 GT1

The Porsche 911 GT1 was a racing car designed for competition in the GT1 class at the 24 Hours of Le Mans and sold as a road car for homologation purposes. The street-legal version was labeled the 911 GT1 "Straßenversion" ("Street version").

History

Porsche debuted the 911 GT1 in 1995, announcing that it would compete at the 1996 24 Hours of Le Mans. In spite of its name, the car actually has very little in common with the 911, its floorpan was taken from the 956/962 Group C car. In addition, the GT1 featured a water-cooled, twin-turbocharged and intercooled, four valve per cylinder flat-six in a mid-mounted position and making about Convert|600|hp|kW|-1|abbr=on. In comparison, the 993 generation 911 GT2, which was otherwise the company's highest-performance vehicle, used an air-cooled engine with only two valves per cylinder and mounted in the rear, which is the traditional layout for the 911.

1996

The new vehicle was an outright success at Le Mans, winning the GT1 class at its debut race, although it lost the overall victory to Joest Racing's Porsche WSC-95 prototype, still a success in that this vehicle used a Porsche powerplant.

The 911 GT1 made its debut in the BPR Global GT Series (the FIA championship's predecessor) at the Brands Hatch 4 hours, where Hans-Joachim Stuck and Thierry Boutsen won comfortably. They followed up by winning at Spa and Ralph Kelleners and Emmanuel Collard triumphed for the factory team at Zhuhai.

The '96 GT1 had around Convert|600|hp|kW|-1|abbr=on and was clocked at a top speed of exactly Auto km/h|330|0 on the legendary Mulsanne Straight in the practice sessions of the 1996 Le Mans 24 Hours Race (presumably on a low downforce setup).

1997

In 1997, the new Mercedes-Benz CLK-GTR was successful in the new FIA GT Championship that replaced the BPR, as it was developed for racing. Mercedes did not enter Le Mans yet with their new car, though. The Porsche did not prove to be as fast in the FIA series, and failed to win a single race, first against the McLaren F1 GTR, and then against the new CLK-GTR.

Porsche made minor revisions to the car for the 1997 Le Mans, including restyling the front end to incorporate "kidney shaped" headlamps like what would appear a year later on the 996 generation 911s, and Boxsters; this version is known as the 911 GT1 Evo (or Evolution). As far as performance goes, the car had the same Convert|600|hp|kW|-1|abbr=on turbo-charged engine, but new aerodynamics on the car allowed the '97 car to be considerably faster than the 1996 model - acceleration was better, although the top speed was still around Auto km/h|330|0 on the La Sarthe Circuit (in the race, the GT1-Evo reached 326 km/h). However, the works cars suffered from reliability problems and did not last the full race distance; a privately entered GT1 managed 5th overall and third in its class, but was beaten by the BMW-backed and powered McLaren F1 GTRs.

1998

Porsche committed themselves to a full blown re-thinking of the vehicle for the 1998 race, as the FIA and ACO abandoned the rule that GT1 cars must be based on a production vehicle. Designed to match the Toyota GT-One and Mercedes CLK-GTR, the 911 GT1 '98 featured radical changes to the bodywork and a new sequential gearbox. In 1998, in spite of improvements to the car, the privately entered Porsches proved to be no match for the works CLKs which also were improved. This was also due to the air-restrictor rules being regarded as unfavourable to the turbo engine. The Michelin tyres of the factory team and especially the Pirelli of Zakspeed were considered inferior to the Bridgestone of Mercedes, which also would dominate in F1 for many years.At Le Mans, it was a different story. The new BMW V12 LM retired with wheel bearing trouble, and the Mercedes CLK-LM vehicles had oil pump troubles in the new V8 engines that replaced the former V12. The Toyota GT-One was very fast but also suffered gearbox reliability problems.

The revised 1998 model, despite being slower than the Toyota or the Mercedes, fulfilled Porsche's slim hopes, taking both first and second place overall thanks to reliability, giving Porsche its record-breaking 16th overall win at Le Mans, more than any other manufacturer in history.

At Petit Le Mans race in Road Atlanta, the 911 GT1/98 of Yannick Dalmas made a spectacular backward flip and landed rear first before hitting the side barriers, as did the BMW V12 LMR at the same race in 2000, and most infamously the Mercedes-Benz CLR at Le Mans in 1999.

The GT1 1998 was set up with higher downforce in the race than the previous two years, which reduced its race maximum speed to Auto km/h|310|0. However, in the 1998 Le Mans 24 Hours test days, the car hit Auto km/h|330|0 on the Mulsanne Straight on a lower downforce setup.

1999

With Mercedes dominating FIA GT1 in 1998, all other entries including Porsche withdrew for 1999. The GT1 class was cancelled, and the FIA GT Championship was contested with GT2 cars. Porsche could have entered at Le Mans, but chose not to try to defend the lucky win of '98 against new machines from other factories.

Champion Racing brought a 911 GT1 Evo to America to race in the American Le Mans Series, but was only allowed to do so as an LMP (Le Mans Prototypes) class entry, where it proved uncompetitive against actual prototypes such as the BMW V12 LMR.

Gunnar G-99

Following Champion's purchase of a 911 GT1 Evo for 1999, Gunnar Racing offered a custom race car to the team with intentions to race in 2000. The car, known as the Gunnar G-99, was a custom-built 911 GT1 with an open cockpit. The chassis was made from scratch yet remained nearly identical to the 911 GT1 mechanically, even using the bulk of the bodyparts. A large rollbar was put over the open cockpit to help protect the driver. A 3.6 litre flat-6 from a Porsche 911 GT3 was used in place of the standard 911 GT1 unit.

However, Champion would instead turn to buying a Lola B2K/10, so the Gunnar G-99 was temporarily abandoned. The car would resurface in the Rolex Sports Car Series in 2002, yet would not be allowed to race until it had a roof again. Therefore Gunnar Racing rebuilt the car with a near identical GT1 roof, and briefly competed in 2003. The car would take a best finish of second in class twice before being retired due to lack of funding.

Street-legal version

Regulations for the GT1 category stipulated that to be eligible, a total of 25 cars must be built for road use. Porsche developed a fully road-legal version, dubbed "911 GT1 "Strassenversion"," and delivered one in early 1996 to the German government for compliance testing, which it passed. The engine had to be slightly de-tuned to meet European emissions laws, although its 700&bhp;PS (400 kW) and dry weight of Auto kg|1100|0 proved to be more than adequate; the vehicle could accelerate to 100 km/h (62 mph) from a standstill in 3.3 seconds on its way to a top speed of 378 km/h (235 mph).

External links

* [http://www.porsche.com/usa/eventsandracing/motorsport/philosophy/history/racingcars/ Official Porsche History of Racing Cars website]
* [http://www.porsche.com/usa/eventsandracing/motorsport/philosophy/history/racingcars/1996-911gt1/ 1996 Porsche 911 GT1 at official Porsche website]
* [http://www.porsche.com/usa/eventsandracing/motorsport/philosophy/history/racingcars/1997-911gt1evo/ 1997 Porsche 911 GT1 Evo at official Porsche website]
* [http://www.porsche.com/usa/eventsandracing/motorsport/philosophy/history/racingcars/1998-911gt198/ 1998 Porsche 911 GT1 '98 at official Porsche website]
* [http://www.bigporsche.com/gt1.htm]