In the early '70s they were runing the awe-inspiring 917s against the might of Ferrari (Watch the film, Le Mans, for some idea of what that was like. Most of the racing action was filmed at the1970 race). The 917 even made a short lived return in the 80s, when Kremer built one for the burgeoning Group C category.
By 1980, their Porsche 935 was king of the GTs in Group 5 (especially the short lived 'Moby Dick' space frame 935 briefly run by the factory) and the 936 was dominating the Group 6 (open sports racers) category. In 1979 a Porsche 935 K3 (modified by the Kremer brothers, the factory having given up developing the 935) actually took first and second in the partly rain soaked Le Mans.
Porsche looked set to continue their domination of sportscar racing into the 80s, when they launched the 956 in 1982.
A development of the open 936, the 956 (and later 962) was the archetypal sports racer and served as the backbone of Group C until its demise. Powered by a flat 6, it proved reliable, fast (enough) and simple enough for privateers to run on sensible budgets.
Unsuprisingly, Porsche, who race to sell cars, were keen to focus attention on their road cars. In 1986, they raced a 959 roadcar at Le Mans. Designated the 961, this car looked upright and odd amongst the sleek Group C cars, but performed well and recorded a Nth placed finish.
In 1994, the Group C Porsche was dead, but the Le Mans GT regulations left a gap big enough to drive a 962 through. The factory promptly obliged. Tagged the Dauer-Porsche 962, after one of the road going 962 conversions, the 1994 entry was little less than the factory's latest development of the 962. Sure, it ran on slightly narrower tyres than a pukka Group C car (like the Toyota it defeated at Le Mans), but it got a whole lot more fuel to use in a stint.
Whilst it complied with the letter of the rules, it clearly infringed the spirit and the ACO made it clear that the 'Dauer Porsche' would not be welcome back in 1995. By then, of course, the aim of winning Le Mans was long achieved.
The arrival of the McLaren F1 in GT racing seemed to take Porsche by suprise. They had a 'GT1' 911, but it was little more than an overboosted GT2 car and performed with astonishing unreliability for a Porsche. The GT2 cars, however, were fairly competitive against the GT competition and usually won by sheer weight of numbers. No-one ever got fired for racing a 911, it seems.
It took the factory until Le Mans, 1996 to come up with an answer to the McLaren and it was to change the face of GT racing forever. Perhaps the factory hoped that road-going cars, modified to race, would really be the answer, but the McLaren was so far ahead of anything else for the road that desperate measures were called for.
These measures resulted in the 911 GT1. First raced at Le Mans, they came tantilisingly close to taking victory in the 24 hours and were so successful in subsequent BPR races (Winning at Brands, Spa and Zhuhai in China, despite not counting for points) that the FIA imposed draconian restrictions on turbocharged cars for 1997.
1997, didn't prove so great for the 911 GT1. The FIA swung the pendulum to far in favour of normally aspirated cars, perhaps not expecting Mercedes to up the ante to dramatically just six months later or McLaren to respond so effectively. Perhaps more painful for Porsche, was the fact that a TWR designed open top prototype, dropped by the factory as a WSC car for the IMSA series in the US (after, ironically, draconian limitations on turbo engines), beat their GT1s at Le Mans, just as it had done the previous year. Apparently, there were tears in the Porsche pit when their lead car burst into flames on the Mulsanne straight.
Uno de los GT1 que tengo en casa (1/18)