The race car that finally won Le Mans for Porsche.
The problem the 917 was built to solve
By 1968, Porsche had been racing at Le Mans for seventeen years without winning the race outright. The company had won class titles, set distance records, and finished on the podium repeatedly. But the overall victory had escaped them. The 24 Hours of Le Mans was dominated by Ford, Ferrari, and Matra — bigger-engined cars with more power than the largest Porsche of the era.
In 1968, the FIA introduced new Group 6 rules with a 3.0 liter displacement limit — too small for the front-running Ford GT40s — and added a separate Group 4 category for "sports cars" produced in at least 25 examples, with no displacement limit. Porsche immediately saw the opportunity. If they could build 25 examples of a Le Mans-spec car with whatever engine they wanted, they could compete on equal terms with Ferrari's 5.0 liter cars and beat them on reliability and aerodynamics.
The car
Design started in 1968 under the direction of Hans Mezger (the same engineer behind the original 911 engine) and Ferdinand Piëch (the Porsche family member who ran the racing department at the time). The result was the 917 — a low, wide, mid-engine prototype with an air-cooled 4.5 liter flat-twelve engine derived from doubling up the 911 flat-six architecture.
The 917 produced approximately 580 horsepower in 1969 trim. The body was aluminum tube-frame construction with fiberglass body panels. The first 25 cars were lined up at Porsche's Stuttgart factory in March 1969 for FIA inspection — the homologation requirement met in a single batch. The 917 was approved for Group 4 competition.
The aerodynamic problem
The first season was a disaster. The 917 was fast in a straight line but unstable at high speed. At Le Mans 1969 — the car's first major race — the long-tail 917 variant lifted at high speed on the Mulsanne Straight. Both factory entries crashed; one fatally. The race was won by a Ford GT40 driven by Jacky Ickx.
Porsche spent the off-season redesigning the aerodynamics. John Wyer's racing team — JW Automotive Engineering, the team that had won Le Mans for Ford in 1968 and 1969 — took over factory support and redesigned the body. The new short-tail 917K (Kurz, German for "short") was substantially shorter and generated downforce rather than lift.
The 1970 win
The 1970 Le Mans was the first overall victory for Porsche. The race took place in heavy rain — at one point, Hans Herrmann set a lap record of 3:23 in horrendous conditions. The factory effort was supported by Wyer's JWAE team and the Salzburg team operated by Louise Piëch (Ferdinand's daughter). Both teams ran 917Ks.
The winning car was the red-and-white Salzburg-team 917K driven by Hans Herrmann and Richard Attwood. The pair drove conservatively through the worst weather, let the field crash and break itself, and emerged at the end having completed 343 laps — 4,607 kilometers — at an average speed of 192 km/h. The win was Porsche's first at Le Mans after nineteen years of trying.
The 1971 win
Porsche won again in 1971 with the 917 magnesium long-tail driven by Helmut Marko and Gijs van Lennep. The 1971 race set a distance record — 5,335 kilometers — that stood for thirty-nine years. That race also featured a pre-race film shoot for Steve McQueen's "Le Mans," with cameras mounted on competing cars during the actual race.
The 917/30 — the Can-Am car
In 1971, the FIA tightened the rules to exclude the 917 from international sports car racing. Porsche pivoted: the 917 was reworked for the Can-Am series in the United States, where engine displacement was unlimited and turbocharging was permitted.
The result was the 917/30 — a twin-turbocharged 5.4 liter flat-twelve producing approximately 1,100 horsepower in race trim and an estimated 1,580 horsepower in qualifying configuration. The 917/30 driven by Mark Donohue dominated the 1973 Can-Am season, winning six of eight races. The car was so dominant that Can-Am rule-makers introduced fuel-economy regulations specifically to slow it down, which Porsche correctly interpreted as the end of the series for them. Porsche withdrew the 917/30 at the end of 1973.
What the 917 left behind
The 917 program lasted only five competitive years — 1969 through 1973. But it transformed Porsche's standing in international motorsport. The 1970 and 1971 Le Mans wins established the company as a serious factory-backed competitor at the highest level. The Can-Am dominance demonstrated their engineering capability beyond endurance racing.
The 917 also created the institutional foundation for everything that came after. The 956 of 1982, the 962 of 1984, the 911 GT1 of 1996-1998, and the 919 Hybrid of 2014-2017 all trace their organizational lineage to the 917 program. The car was the start of Porsche's modern racing identity.