Although incorporating certain lessons learned from the preceding 904 GTS programme, Porsche’s new-for-1966 906 model–officially designated the Carrera 6–was notably divergent in its mechanical composition. Whereas the 904 employed a ladder chassis with a bonded fibreglass body, the 906 used a more conventional multi-tubular frame, clothed in unstressed fibreglass of nominal thickness to minimise weight. Some 65 chassis would be constructed, of which 52 were fitted with 2-litre, six-cylinder carburettor engines, nine equipped with fuel injection and four with experimental 2.2-litre eight-cylinder motors. Significantly, in customer specification, the new car offered a weight reduction of some 200 pounds relative to the outgoing 904.

Competition success was immediate, with a 2-litre class win–and sixth overall–achieved on debut in the Daytona 24 Hours, with further class wins forthcoming in the Sebring 12 Hours and at the Monza, Spa, Nürburgring and Paris 1,000 Kilometre races. If, inexplicably, there was any doubt as to the new car’s abilities, then outright victories at the Targa Florio and Circuito del Mugello–not to mention fourth overall and the almost inevitable class win at Le Mans–surely put these to rest. Indeed over the next two seasons, until its replacement with the 910, the 906 became arguably the most accomplished and versatile of all two-litre Sports Racing cars.

The car offered here, chassis 906-115, was completed at Zuffenhausen on 9 March 1966, to the order of keen Italian amateur racer and hillclimber Ermanno Spazzapan. Invariably competing under the pseudonym of “Mann”, Spazzapan enjoyed a strong affiliation with Porsche, having previously campaigned both a 356B 2000GS and a 356 Carrera Abarth GTL in Italian domestic events in 1964 and 1965. However, his purchase of 906-115 in the Spring of 1966 represented not only his first known experience of a Sports Prototype, but also a significant step up in terms of performance.

As with other customer specification 906s, 906-115 was fitted with a six-cylinder Type-901/20 engine, which employed a sand-cast magnesium elektron crankcase, forged steel crankshaft, titanium connecting rods, forged alloy pistons and dry-sump lubrication. A compression ratio of 10.3:1 afforded a power output of some 210 horsepower at 8,000 rpm, while a five-speed Type-906/1 gearbox transmitted this to the road.

“Mann” made his debut in 906-115 at the Stallavena-Boscochiesanuova hillclimb on 17 April, in which he finished second in class in the over-2000cc Sports Racing car class. The remainder of the season encompassed some nine further events–eight hillclimbs and one race–and the pair became a regular sight on the Italian hillclimb scene. The Antignano-Monte Burrone round in June represented the season’s highlight, with an outright win, while the event from Spazzapan’s hometown of Vittorio Veneto, in Treviso, to Consoglio yielded a noteworthy second place overall. Third place finishes were also achieved at Cividale-Castelmonte, Bolzano-Mendola and at the Coppa Alpe del Nevegal, while the season’s sole circuit-based event saw the pair finish second in class at the Coppa Agip at Vallelunga, behind the victorious sister 906 of “Noris”.

However, after only a single season of ownership, Spazzapan opted to sell 906-115 to his fellow countryman Ennio Bonomelli in early 1967. The latter would later emerge as something of a Porsche specialist, driving a variety of models including a 908/03, 910 and 911 RSR, and winning the 1968 Italian GT Championship in a 911S, yet it appears that he drove 906-115 on only three occasions, each of which were hillclimbs. Instead, the car was primarily entrusted to Antonio Zadra–occasionally known by his pseudonym of “Khandaru”–and Giuseppe Dalla Torre.

The car’s race debut under its new ownership came in a 20-lap Unlimited Sports Car race at Innsbruck in May 1967, although regrettably its finishing position is unknown. Next, however, was the altogether more serious prospect of the 500 kilometres of Mugello; then a round of the World Sportscar Championship. Held on the daunting 66.2 kilometre road circuit, the event attracted no less than 111 entries, including two factory-entered Porsche 910s for Schütz/ Mitter and Neerpasch/ Stommelen, two Scuderia Ferrari 206 Dino Competiziones for Scarfiotti/ Vaccarella and Klass/ Williams, and three Autodelta Alfa Romeo T33s. At the conclusion of the gruelling 8-lap, near four-and-a-half hour race, Schütz and Mitter prevailed–with their 910-mounted teammates second and the Prototype-class Porsche 911R of Elford and van Lennep third. However, “Khandaru” and Dalla Torre drove superbly to finish tenth overall and third in class; beaten only in their category by the similar 906s of Cella/ Biscaldi and Nicodemi/ Facetti.

A little over a month later, “Khandaru” drove the car to a fine 14th overall and seventh in class at the Ollon-Villars hillclimb, while the season rounded off at Aspern, in Austria, in early October. There, a high quality entry for the 40-lap Sports Car race included the likes of Dieter Quester and Peter Schetty–in works BMW and Abarth respectively–but “Khandaru” and 906-115 acquitted themselves admirably, finishing ninth overall and third in the 2-litre class.

Intriguingly, the 1968 season was scheduled to start with an entry into the Nürburgring 1,000 kilometres–once again with “Khandaru” and Dalla Torre driving–but evidently 906-115 failed to appear. However, in late-June, it contested the Coppa Gallenga at Vallelunga, where “Khandaru” finished a fine third overall and first in class behind the Ferrari 206S Dino of Ferdiando Latteri and the Porsche 910 of Antonio Nicodemi. Disappointingly, a return to the Circuito del Mugello in late July proved frustrating for the car’s customary pilots, ending as it did in an early retirement.

Arguably 906-115’s finest hour came in the Imola 500 kilometres, held at the scenic Emilia-Romagna circuit in September 1968. A fine race entry included three privately-entered Porsche 910s–one of which was to be shared by factory driver Vic Elford–and three Autodelta Alfa Romeo T33/2s driven by the all-star team of Vaccarella/Zeccoli, Giunti/Galli and Casoni/Dini. Once again “Khandaru” and Dalla Torre were paired in the car; both drivers and car excelling to finish a fine fourth overall–and first in class–behind the three Alfas. The car’s final contemporary race season concluded in Austria with races on consecutive weekends in Aspern and Innsbruck, in early October. Ranged against some of the most respected Sportscar drivers of the day–including Merzario, Marko and Hezemans–Zadra finished a respectable ninth, and third in class, in Aspern and seventh–fifth in the 2-litre class–in Innsbruck.

The rapidly changing Sports Prototype landscape of the late 1960s–and in particular the increasingly important role of aerodynamics–rendered both the 906 and many of its Group 4 contemporaries increasingly uncompetitive in International Sportscar racing. However, the 1970s saw burgeoning interest in newly-designated “Historic” racing cars and, against this backdrop, 906-115 was subsequently located and purchased by Bergamo-based enthusiast and broker Corrado Cupellini. Having retained ownership for several years, Cupellini sold 906-115 to German Porsche luminary Bernd Becker in 1977; the car representing a fitting stablemate for the latter’s ex-Ben Pon 910. Becker would retain 906-115 for almost a quarter of a century, regularly racing the car throughout Europe and, on occasions, in South Africa, until its sale to German-based brokers PS Automobile in 2001. In their custody, 906-115 was subjected to a comprehensive rebuild; the retention of its original GRP panels, engine and gearbox all being noted at this time.

Duly completed and returned to its original colour of Grand Prix White, 906-115 reappeared in the 2002 Tour Auto, before being sold to Frenchman Alain Salat in 2004. In his custody, the car contested the Tour Auto again, prior to its acquisition by an anonymous French collector in 2007, and subsequent purchase by Swiss-based collector Carlo Perego in 2014. The latter retained the car for some seven years, before selling it to the most recent previous owner in 2020.

In his custody, 906-115 has been fastidiously maintained by marque experts Road Scholars of Durham, NC, at a cost of over $60,000. This has included–but is not restricted to–rebuilds of the carburettors and steering rack, the replacement of the rear crankshaft oil seal, clutch and front suspension ball joints, and the performance of general engine calibration work. Remarkably, in September 2020, the car joined 906-109, 906-110 and 906-158 for a memorable 300-mile road trip between Vail and Aspen, Colorado; the dramatic scenery of the Rockies providing an appropriately Alpine context in which to celebrate 906-115’s formative years. With the current owner, the car’s original windscreen was replaced due to a crack, but has been retained for safe keeping.

Highly accomplished, reassuringly uncomplicated and commendably practical, the Porsche 906 remains one of the greatest of all competitive all-rounders–not to mention perhaps the supreme giant-killer. Furthermore, its sheer versatility renders it ideally suited to–and highly eligible for–some of the world’s greatest historic events. In the case of 906-115, these attributes are further supplemented by its fascinating competition history and truly extraordinary originality. Indeed, the latter is confirmed by the retention of both its original engine and gearbox–serial numbers 906-113 and 906-110 respectively–as at the time of cataloguing, despite the passage of almost six decades, and a fascinatingly varied competition career.