The GT1 class in endurance racing spawned some of the fastest and most radical road-going cars ever made, with as prime example the Porsche 911 GT1.
Porsche wasn’t pleased with the outcome of the 1995 edition of the 24 Hours of Le Mans, where their iconic 911 was thoroughly beaten by the McLaren F1 GTR. Not only became the British marque the first in the history to win Le Mans at the first attempt, but it also managed to claim four out of the five top positions: first, third, fourth, and fifth. Impressed by McLaren’s performance, Porsche acknowledged their cars were no longer going to be competitive, the 911 wasn’t able to keep up with the British supercar and the 962 used by Dauer Racing was outdated. Something new was needed, more powerful, faster — something radical.
Norbert Singer, who was in charge of Porsche’s racing division, was tasked with the development of a car based on the 911 which could match the McLaren F1. The German engineer had been involved in every Porsche win at Le Mans. He helped Porsche with its first Le Mans win with the 917, was responsible for the 935 and designed the bodyworks of the 956 and 962, which won Le Mans an impressive seven times. It was also Singer who discovered a loophole in the GT regulations which allowed him to build a purpose-built race car set to assault Le Mans.
In order to comply with the regulations manufacturers of GT1 cars were required to build at least one street-legal version which was on sale to the general public. Singer exploited this rule and turned it upside-down: instead of modifying a road car into a racing car (like the McLaren F1, Jaguar XJ220 or Ferrari F40), he designed the racing car first. The road-going derivative was not more than a practical detail as it served only a ticket into GT racing.
Singer and his team realized a mid-engined car would be more competitive that a rear-powered one, this would benefit the distribution of weight and provided more working space for the aerodynamics. The engineers in Zuffenhausen started with the front-end of a Porsche 993 GT2, designed a new tubular frame and moved the engine to the middle, just behind the driver. The monocoque was made from steel, but most of the bodywork was made from lightweight Kevlar and carbon-fiber. A diffuser was fitted under the rear of the car, which was derived from a 962. The downforce was further enhanced via a massive adjustable plastic rear wing.
The water-cooled twin-turbo 3.6-liter flat six provided 600 horsepower at 7.200 rpm and was paired to a six-speed gearbox, which transferred the power to the rear wheels. With a weight of only 1050 kg, the 911 GT1 was able to hit a top speed of approximately 320 km/h while a sprint from standstill to 100 km/h would take 3.7 seconds. Interestingly, these performance figures were below of its main competitor the McLaren F1. Nevertheless the Porsche 911 GT1 would prove to be fast.
When the new Porsche entered the circuits for the first time in 1996 it wasn’t greeted with much enthusiasm. Many competitors believed the 911 GT1 wasn’t in line with the spirit of the regulations — this wasn’t a road car modified for racing, but a purpose-built racer which maneuvered clever through the regulations. Meanwhile, a street-legal version was built and delivered to the German government, which tested the 911 GT1 Straßenversion (Street Version) and declared it roadworthy. Here it was: Porsche received official backing which proved that the 911 GT1 was a street-legal car. The 911 GT1 was debuted successful at Le Mans, the spectacular Porsche won its class and was overall only beaten by the Porsche WSC-95 prototype. After the Le Mans success the 911 GT1 went on to win a few others races as well.
But a new and more advanced version of the 911 was already in the pipeline, and a few other carmakers had started building their own homologation specials as well. Whereas the international GT racing was initially dominated by modified versions of production cars like the Ferrari F40 and the McLaren F1, it now became the realm of advanced prototypes disguised as street-legal cars or the so-called homologation specials. This will covered in the next chapter of GTspirit’s Remarkable Cars.