Last Porsche 917 to race at Le Mans is going under the hammer

The iconic Porsche 917 was the German marque's first prototype racing car to win the fabled 24 Hours of Le Mans outright in 1970. It would repeat this feat in 1971.

The formidable track weapon won many other events, including two victories at the 24 Hours of Daytona in the World Sportscar Championship, until regulation changes saw it retire at the end of the 1971 campaign. Heavily modified versions of the 917 continued to race with much success in the US' unrestricted Can-Am series for another two years.

In 1981 an unexpected technical loophole opened up at Le Mans, allowing the mighty Porsche 917 to return to France's Circuit de la Sarthe for one last shot of glory.

Constructed by Kremer Racing with full co-operation from Porsche, the resultant 917 K-81 was heavily updated to conform with Group 6 regulations and sported improved aerodynamics, side skirts, contemporary slick racing tyres, a stiffer aluminium spaceframe chassis and bespoke brakes and suspension components developed during the Can-Am era.

The Porsche factory provided two original Type 912 flat-12 engines — one of a 4.5l capacity and the other 5.0l — to which an original Type 920 five-speed transaxle was mated. A power output of around 427kW gave the 917 K-81 decent on-paper performance. 

Unfortunately, during qualifying for the 1981 24 Hours of Le Mans, the pace of the car was lacking on the 6km Mulsanne Straight due to short gear ratios and significant drag from its oversized rear wing. Driver Bob Wollek qualified in 18th position, trailing the pole-sitting Porsche 936 by 17 seconds per lap and the sixth-placed 935-K3 by 10 seconds.

With revised gear ratios installed for the race, the car's top speed improved. Wollek managed to climb to ninth place overall during his stint, but other teammates couldn't match his pace. The team also faced setbacks, including running out of fuel and damaging an oil pipe. Eventually, due to significant oil loss and resulting engine damage, the car was retired from the race, marking an unfortunate conclusion to its participation in the event.

The 917-K81 remained in Kremer’s possession for several years before its sale to prominent 1960s Porsche 906 and 910 racer Bill Bradley. Acquired by the current owner in 2011, the race car has been under the care of Crubilé Sport, renowned Porsche specialists based in Gazeran, France. Its use has been limited to occasional track days and non-competitive events since then. Notably, it participated in the Le Mans Heritage Club Concours at the 2014 Le Mans Classic, where it received the Special Jury Prize.

Recently its 5.0l engine underwent a complete rebuild by Crubilé Sport, with detailed invoices available. The rebuilt engine was statically tested in February, demonstrating a significant increase in power compared to factory built units of its time.

The 917-K81 is meticulously maintained and presented in impeccable condition. It stands as a unique postscript to one of Porsche's greatest Sport Prototypes. Eligible for historic racing events, it offers a highly competitive and exhilarating entry. Additionally, it serves as a spectacular centrepiece for any discerning competition car collection.

Well, provided you can fit the bill: RM Sotheby's estimates the nugget of Porsche racing history will sell for $3.75m to $5.5m (R70.7m–R103.6m).