On March 13, 1969 at the Geneva International Motor Show, Dr. Ing. h.c. F. Porsche unveiled a car that would exceed its creator's wildest dreams and turn out to be one of the most iconic race cars of all time: The Porsche 917.
Project 917 began in June 1968, in response to an edict from the international motor sports authority, known as the Federation Internationale de l'Automobile (FIA), which had announced a class for 'homologated sports cars' with up to a five liter engine capacity and a minimum weight of 800 kilograms.
Under the supervision of Porsche family member and gifted engineer Ferdinand Piech, the FIA-stipulated minimum 25 units of the new race car would be completed by April 1969 so that the 917 could race during the 1969 international season. Initially, Porsche had built six cars and had 'all the bits and pieces to build 19 more for homologation,' according to Rico Steinemann, Porsche's Racing Manager at the time. 'The FIA then decided, no!' All 25 cars would have to be built. As all of the racing departments resources were being utilized, the workers to build the cars would have to come from elsewhere.
'We put together apprentices, messenger boys, bookkeepers, office people and secretaries,' remembered Steinemann years later. 'Just enough people, taught just enough to put together 25 cars!'
After the inspection, all but two of the cars were completely disassembled and rebuilt by the factory race team mechanics.
While the 917 retained Porsche's traditional horizontally opposed, air-cooled 'boxer-style' engine configuration, the 4.5 liter, 520 HP 12-cylinder engine was bigger than any engine Porsche had built. The frame, designed more for durability than the light weight, was constructed of TIG-welded aluminum tubing (later switched to magnesium), while the fiberglass re-enforced resin bodywork weighed in at a total of 93 pounds.
The 917 shape underwent constant evolutionary changes, with Porsche engineers developing different body configurations to best meet the demands of the varied circuits on the World Championship calendar. The so-called short-tail, or 'Kurzhack' bodywork, was designed for his downforce tracks such as Watkins Glen and Brands Hatch, while the original 'Langhack' long-tail bodywork was further developed to optimize straight-line speed and stability on the long, ultra-high speed tracks like LeMans with its 3.5 mile long Mulsanne Straight.
Success was not immediate for the 917. After initially dropping out of its first three races due to technical problems, the 917 success story began in August 1969 at a 1000-kilometer race at the Osterreichring with a victory by Jo Stiffert and Kurt Ahrens.
This series of victories in 1970 began with the Daytona 24 Hours and continued at Brands Hatch, Monza, Spa, the Nurburgring Nordschleife, the Targa Florio, the epic 24 Hours of Le Mans, Watkins Glen 6-Hour and once again at the Osterreichring. However, the season's high point was the long-desired overall win at the Le Mans 24-hour endurance race, a trophy that Hans Herrmann and Richard Attwood brought home to Zuffenhausen on June 14, 1970. The number 23, 917K short-tail model, painted in the red and white colors of Porsche Salzburg, successfully fought off the combined factory efforts of Ferrari, Matra and Lola, but also battled horrible weather conditions during hte race. The 917 had fulfilled its charter by not only winning the 24 Hours of Le Mans, but by also winning the World Championships of Makes.
The 1971 season was once again dominated by the 917 as Porsche defended their World Championship of Makes' crown by winning eight out of the ten races on the schedule. For the second year running, a Porsche 917 was victorious at the Le Mans 24-Hour race - this time with GIJs van Lennep and Dr. Helmut Marko driving. They set world records with an average speed of 222 km/h and a total of 5,335 kilometers driven, which are records that still stand today.
When the European FIA regulation for '5-liter sports cars' expired at the end of the 1971 season, it brought the 917's world of Makes' championship career to a close.