Since its introduction in 1964, the Porsche 911 has proven successful in virtually every form of motor racing, from prestigious international endurance contests to the most punishing off-road rallies. Central to that success were Porsche’s own competition and development efforts, and almost from the model’s inception, the factory has built specialized variants to explore the 911’s performance, durability, and adaptability under demanding conditions.

The first major step in this process was the development of the 1967 911 R, an ultra-lightweight experimental machine that led directly to the specialized T/R and S/T models and, beginning in 1973, the formidable RSR. Together, these cars established a lineage of competition-prepared 911s, providing the technical foundation for Porsche’s growing dominance at the highest levels of international motorsport.

The 911 presented here belongs to a fascinating and little-known chapter in that story – one that quietly laid the groundwork for Porsche’s endurance and rally successes of the 1970s. According to a copy of the Porsche Kardex, chassis 119300004 was completed in June 1968, finished in Blutorange (Blood Orange, code 6809 B), and originally equipped with a two-liter, fuel-injected Type 901/10 911 S engine (no. 6390004), a competition-type gearbox (no. 9284107), and Pirelli tires.

A copy of a 1994 letter from Porsche, retained in the car’s file, confirms that this chassis belonged to a group of 10 pre-series vehicles built between April and June 1968 and retained by the factory’s Research and Development department for testing purposes. Of these 10 cars, one example, 119300003, is known to have been part of Porsche’s victorious three-car works entry in the 1968 Marathon de la Route. Crucially, the letter confirms that 119300004 carried the internal designation 911 GT-S.

Further supporting this classification, the Kardex for chassis 004 bears the notation Versuch – German for “Test” or “Experimental” – and shows an earlier six-digit chassis number (320017) crossed out and replaced with 119300004. This is consistent with Porsche’s practice of constructing these 10 pre-series 911 GT-S cars using shells that had been originally assigned six-digit serial numbers.

While available factory documentation does not specify the precise duties of 004 during the approximately 14 months it remained under Porsche ownership, correspondence on file strongly suggests that it was used for a variety of testing, training, and development purposes, with particular emphasis on endurance and off-road rally applications.

A letter from Porsche mechanic and racing driver Günther Steckkönig describes 004 as an “experimental car in the Porsche developing department” and states that it was used by famed rally driver Pauli Toivonen as a practice car during the Tour de Corse (October 1968), the Monte Carlo Rally (December 1968–January 1969), and the Acropolis Rally (May 1969). Steckkönig further notes that he himself used 004 as a service car during Porsche’s works effort at the 1969 Acropolis Rally.

In September 1969, Porsche sold chassis 004, by then fitted with engine no. 6390650, to its first private owner, Eduardo Dibós Chappuis of Peru. Known as “Chachi,” Dibós was a prominent figure in both motorsport and public life. Born in 1927, he studied engineering at MIT, competed internationally in events such as the Buenos Aires 1000 Km and the 24 Hours of Daytona in machinery ranging from a Ferrari 250 GT SWB to an Alfa Romeo Tipo 33/2, raced in NASCAR, and later served as Mayor of Lima from 1970 to 1973, as well as President of the Peruvian Automobile Club.

That same month that he acquired the ex-works 911 GT-S, Dibós entered it in the Caminos del Inca Rally, with co-driver Werner Bross and wearing race no. 520.

The car remained in South America for several decades before being discovered in the late 1990s by noted Porsche restorer Roy Sanders of Marietta, South Carolina. By that time, it had been modified with 3.0 RSR-style bodywork. Over subsequent years, Sanders undertook extensive research into the car’s origins, corresponding with leading Porsche historians and former factory personnel. Among them was ex-works mechanic Lothar Runft, who recalled maintaining 004 for Dibós in 1969 and remembered it being equipped, during its factory period, with hydropneumatic front suspension – an intriguing detail shared with the famed Marathon de la Route cars.

In 2004, Tommy Trabue acquired 004 and commissioned Sanders to carry out a comprehensive restoration. Completed in 2022 and documented by extensive correspondence, invoices, and photographs, the restoration returned the 911 GT-S to period-correct specification, finished once again in Blood Orange and fitted with a correct type 901/10 engine (no. 6392082), a 100-liter aluminum fuel tank, roll bar, aluminum deck lid with external hinges, and driving lamps.

Unshown since its restoration, chassis 004 represents a rare opportunity to acquire a historically significant experimental Porsche – an ex-works 911 GT-S with documented factory testing use, close technical and conceptual ties to the 1968 Marathon de la Route entries, and a period rally entry by a noted international driver.