The Porsche 906, sold as Carrera 6, with a 2-litre flat six-cylinder Type 901 engine compared to the F4 in its predecessor Porsche 904 Carrera GTS, is a Group 4 Sports Car from Porsche announced in January 1966 for the 1966 World Sportscar Championship. The street-legal racing car met homologation requirements of the FIA like space for luggage and carrying a spare wheel (as did the Porsche 917 in 1969). When the required minimum number of at the time 50 cars was produced, of 65 in total, homologation came into effect in May 1966.
In earlier races, the already numerous 906 had to be entered in the Group 6 Sports Prototype class. Later, the factory also entered modified 906 as prototypes, especially as lightweight hillclimbing spyder, with current Formula 1 suspension parts and wheels, eight cylinder engine, or long tail for Le Mans. Already by August 1966, new prototype class chassis were called Porsche 910.
Together with results of the 904, the 910 and even the 911, the 906 won all 2 litre classes of the 1966 World Sportscar Championship and the 1966 European Hill Climb Championship. Competition from the comparable Ferrari Dino 206S, also intended as Gr.4 sportscar as indicated by the S, materialized only in the Gr. 6 prototype classes as Ferrari built only 18. Privateers in 906 helped Porsche win also the 1967 World Sportscar Championship 2 litre sportscar class which was discontinued in 1968.
History
Prior to the Porsche 906 was the 904 which achieved many racing victories. At the age of 28, Ferdinand Piëch, the grandson of Ferdinand Porsche was given the important job of being in charge of the development of the new Porsche racing cars.
Constructing the new car with the fiberglass helped with things such as structural support as well as looks because it was all placed by hand instead of having an uneven paint job done to it.
The finished product weighed around 580 kg (1,280 lbs), which was around 250 lbs lighter than the 904.
Racing history
thumb|left|Porsche 906 (906-120), rear view
The 906 had several racing careers, with the one as Group 4 sportscar up to 2000cc raced by dozens of customers being the one it was designed for, the most prolific (one overall World Sportscar Championship race win, at the 1966 Targa Florio) and the longest.
The 906 helped Porsche win the 1966 World Sportscar Championship in both 2-litre-classes with a perfect score of 42 points, the International Manufacturers Championship for prototypes over Ferrari, and the International Sports Car Championship Division II (1301 to 2000cc) over Alfa Romeo and Lotus, as the Ferrari Dino 206S never was homologated and always had to run as prototype.
In addition, a 906 Bergspyder prototype was raced by the factory already in late 1965 and early 1966 European Hill Climb Championship heats, while the Sportscar version won its class in 1967 and 1968.
906 as Gr.6 Prototype
The first use case for the 906 was running as prototype, inevitable before the Sportscars homologation was achieved by May 1966, and then later on to test or use improvements that were outside of homologation, like fuel injection, engine size and type, long tail body, new Formula-1-like wheels etc. By summer of 1966, new 906-like chassis built by the factory were called Porsche 910.
A few 906 also ran as prototype over 2000cc when a 2200cc engine was used, mainly the Typ 771/1 flat-8-cylinder, later also the F6.
The 1966 World Sportscar Championship began early, but at least one 906 was in Florida by 6 February 1966 for its debut in the 1966 24 Hours of Daytona. The new Carrera 6 finished 6th overall, behind the big-engine factory Fords and Ferrari, ahead of the factory-904s, and won its class against Ferrari Dino 206 Ps. They secured eighth overall to win its 2.0-liter class in 1969.
Construction
Unlike previous racing Porsches, the 906's body was tested in a wind tunnel, resulting in a top speed of at Le Mans, quite fast for a 2-liter engine car. At the time it showed a close resemblance to future Porsche racing cars. As in the Mercedes-Benz 300SL, gull-wing doors were fitted, and the mid-ship mounted engine was covered with a large plexiglas cover. The Porsche 906 was fitted with an 901 engine that actually came from the Porsche 911R just with a few modifications done to it. These changes included some exotic metals (titanium) in the connecting rods and the crank case (magnesium) to help the car perform at a higher level.
References
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