
Rolf Sprenger was a versatile engineer whose Porsche career was founded almost entirely on customer service. “If I want a trailer (caravan) with a swimming pool, Herr Sprenger will build it for me,” so said Peter Schutz to a potential client, while Sprenger looking on, would groan inwardly: yet another customer whose expectations had been over-excited would have to be brought down to earth. But, although he was the man who devised the highly successful Sonderwunsch scheme, and ran it for many years, there is far more than the special wish department to Rolf Sprenger’s career.

“You know I was a mechanical engineering apprentice at Bosch,” he says, “and then Bosch sent me to Sims & Gray in London, a Lucas subsidiary developing fuel injection for diesels.”
The advent of the first emissions control fuel injection was the next step for premium car makers, and with his background Sprenger could have gone to Mercedes-Benz. Instead, he worked briefly at NSU on the Ro 80’s injection before joining Porsche in July 1967. He was made assistant to Hans Klauser, a senior engineer and Konstructionsbüro stalwart from the pre-war years. Within eighteen months, and at the age of 28, he was promoted to be manager of the Reparaturwerkstatt, one of the main duties of which was technical modification of customer cars. The Reparaturwerkstatt was on the floor below Ferry Porsche’s office and Sprenger recalls how, after he had been appointed, Ferry called him in to explain what he expected: “He said ‘I want all Porsche customers to come here and you to give them outstanding service. Make our reputation with that.’”

Sprenger would indeed do just that, but in 1969 he was simply stunned to be before the company’s founder and to have such a mission confided in him. “It was a wonderful start: I can still feel a frisson of emotion when I think about it today fifty years later. Imagine the boss confiding in a beginner like me! Porsche was truly a family company then, and even with the AG (when family members withdrew from management positions in 1972) there was no change in a practical sense – older people knew Ernst Fuhrmann from his previous time at Porsche, and Helmuth Bott (promoted to technical director) was a familiar figure. But I did miss reporting to Ferry and his visits to the workshop.”

Porsche’s first managing director, Ernst Fuhrmann, is often seen as a controversial figure, but Rolf Sprenger remains positive about him.
“For me he was very approachable, an engineer’s engineer. You could talk to him and he would give you responsibility for a project. He was also realistic: he knew the air-cooled engine could not last forever. But on the other hand, the 928 was too futuristic, too big. We employees learned that because of the 928 the family had to get rid of him. But he did a lot for Porsche and that V8 was one of the great engines. I liked Fuhrmann: he was always supportive of what we were doing in the Werkstatt; I’m sure working with him on an engineering level was easier than on a business level.”

The Werkstatt also encompassed customer racing service. Sprenger continues: “In the days of Edgar Barth it was based at Kornthal – young Jürgen even worked there until Huschke von Hanstein took him under his wing in the press department. In 1969, the racing service was merged with the Reparaturwerkstatt, so as well as fitting tuning kits to 911Ss, we built client competition cars too.”
This included the famous RSRs, both the 2.8 and 3.0 versions. These were taken off the Zuffenhausen production line as standard RS 2.7s and 3.0s and sent across Schwieberdingenstrasse to Werk 1 for conversion to RSRs.
Not all work involved out and out racers: in 1979, Porsche designed a tuning kit for disgruntled SC owners who complained the new 911 had 20 bhp less than the previous 3.0 Carrera. The object was to match the 210 bhp of the mechanically fuel injected 2.7, but not wishing to advertise the fact, the kit, which involved installing larger bores and a higher compression ratio, was advertised through the grapevine: fitting had to be carried out at Sprenger’s Werkstatt, not by the dealers. There was also an element of countering aftermarket tuning kits from Max Moritz and in particular Alois Ruf.

“It was not an especially successful exercise,” says Sprenger today. “It was expensive, adding 20% to the price of the SC and I don’t think we did more than a few hundred. Once Porsche uprated the SC to 204 bhp, we didn’t fit many more.”
More exciting was work transforming the 930 Turbo into the formidable Group 4 934. By the time this was superseded by the 935, preparation of these racers was becoming quite an operation involving aerodynamics specialist Norbert Springer and chassis engineers like Roland Kussmaul.

“We used to see team managers or owners like Georg Loos and Vasek Polak regularly and the drivers too: I remember Toine Hezemans, Herbert Müller, Rolf Stommelen and John Fitzpatrick. I got on particularly well with him.
In 1981 customer racing moved off to Weissach, coinciding with Peter Falk’s appointment as director of motorsport, a rationalisation which was logical. Under new CEO Peter Schutz, the role of motorsport was expanded and the Werkstatt was busier than ever with customer upgrades which were often for additional equipment rather than engine and suspension work. What had occasioned this development was the 930 Turbo, launched in 1975. Originally conceived for racing and to promote the 911, that is until new 928 model was ready, the production 930 was intended simply to reach sufficient volumes to meet homologation norms. However, reaction to the turbocharged 911 exceeded all expectations: Porsche’s target of 1000 units in the first year of production was reached with six months. The turbo had found a new and rich clientele for the 911: despite being a fully equipped model with air conditioning, leather upholstery and top quality stereo, Sprenger found that increasingly these new Turbo owners were turning to Porsche to customise their already exclusive Porsches. And there seemed almost no limit to the money some of these clients were ready to spend.

“I began to see a pattern,” said Sprenger. “I realised that if we started to stock certain parts, we would get them cheaper – buying twenties rather than ones or twos always resulted in a better deal, and we could offer faster service.”

Ernst Fuhrmann had always been very responsive to customer requests – in the 1970s it was often a question of engineering, of which perhaps the most extreme example was the Turbo based on a 2.7 RS shell built for Herbert von Karajan. Under Peter Schutz though, the whole operation moved up a gear. Schutz, very much more focused on the US market, saw lucrative possibilities which coincided with other ideas he had about Porsche’s North American image, such as getting into private aviation.

“To deal with clients who wanted to upgrade their Porsches we created a special department, the Sonderwunsch department, which was fairly open-ended about how far clients could customise their Porsches.”
Money was still in short supply in Porsche and it was 1984 before the first comprehensive catalogues and literature could be drawn up. The basic upgrades besides paint schemes would consist of wooden or leather faced dashboards and door panels or building in of car phones, then bulky, cumbersome devices. Neat drawers for cassettes or later, compact discs, would be incorporated in the doors or in the facia above the gear lever filling the irritating gap which was a feature of the standard 911 cabin until the 996. The final run of 928s had the more integrated front and rear bumpers, a styling improvement that originated from a customer special order.

A special order on Turbos was the Dampfrad, a control wheel which turned up the boost and was situated on the console beside the gear lever. This iconic knob was effectively the nearest you could get on a production car to an ejector seat switch, and symbolised everything that was excessive about the 911 Turbo. Sometimes, absolute luxury was no object. One Middle Eastern potentate ordered a solid gold gear knob costing DM 25,000 (£8000) as the pièce de résistance in a cabin that was almost a parody of opulence. Sprenger recalls that he decided that gear knob could not possibly be fitted to the car for delivery: it would have to travel, if not in the diplomatic bag, then by other highly secure separate means, “otherwise it would have disappeared for certain on the way!”

Many of the Sonderwunsch ideas became part of Porsche production. The stitching which is a feature of current cars has its origins in the special-order cars of the 80s, and the hardtops for Cabrios began as special orders from customers who wanted to be able to use their convertibles in winter. Rolf Sprenger explains how he and colleagues would sit down with customer and work out a specification and he laughs as he remembers just how much extra kit they were able to sell to some enthusiasts. He also recalls meeting a veritable who’s who of the great and famous as they came to place orders with the Sonderwunsch department. Sir Anthony Bamford of JCB, had a number of cars including a Flachbau, the flatnose: “We started those,” Rolf added proudly. Indeed, 2000 flatnoses were built altogether over ten years. Something of a curiosity today, the flatnose look came from the all-conquering Porsche 935, the most successful racing car of the 1970s (and perhaps one of the two or three of all time) and which underpinned the reputation of the 911 Turbo. The 935 would also lead to a difficult request like von Karajan’s lightweight Turbo, for another car that Porsche really did not want to build. Mansour Ojjeh, a Saudi national, asked Zuffenhausen to build him a road-going 935. However, Ojjeh as owner of Techniques d’Avant Garde TAG and Porsche’s partner in the very successful F1 engine programme with McLaren, was no ordinary customer. It was left to Sprenger to resolve this complicated design.
“I put it to Schutz that we could take a 930, build into it as much of a 935 as we could then obtain single vehicle homologation. That at least was the theory and in practice it worked: we got it licenced and Ojjeh was able to drive back to Paris in it.”

Ironically after all the effort, the Ojjeh 935 would cover very few miles, spending most of its early life shuttling occasionally between the Ojjeh residences in Paris and Monaco. “I remember, I once had to rescue that 935 from the underground carpark of a ski resort,” smiles Sprenger. “It had hydraulically adjustable suspension and in the extreme cold it wouldn’t go back up so Ojjeh couldn’t get up the ramps and out of the garage.” The Sonderwunsch manager’s life was punctuated with such customer emergencies.
“Much of the Sonderwunsch work went to the US,” he continued. “At first the PCA disliked Sonderwunsch intervention because it held up deliveries, but then they saw the light and realised there was money to be made: when the dollar was worth three Deutsche Mark, both we and they were making great profits.”

In some respects, Sonderwunsch was in competition with the tuners, not just Ruf but exponents like Gemballa, Techart and the Swiss Sportec. “The trouble was,” says Sprenger, “they would up the horsepower without improving the brakes and do things with aerodynamics that were potentially very dangerous as none of them had wind tunnel testing facilities. We could do it at Porsche because if we upgraded the turbo we would uprate brakes and aerodynamics at the same time. If for example the enhancement programme turned out 500 bhp 959s, and it did, you could be certain that all the dynamics involved had been similarly enhanced. Norbert Singer used to say of some of the wilder tuner offerings that the designs would take off at 250 km/h. Porsche obliged Ruf to remove the Porsche crest and Wiedeking waged a long campaign against Techart. The tuners are more careful now, but we still don’t like them.”
From 1989, Sonderwunsch was renamed ‘Exclusive’ as it was felt a more internationally understood term would help marketing and in any case the operation had to adapt: the winds of change were beginning to blow and special wish requests were becoming harder to fit into production schedules.

“It was already difficult with the 964 and by the 993 (where there was almost no let-up in production before the 996) we were struggling to get space in manufacturing,” explained Sprenger.
Nevertheless, two great cars from this period, the Turbo Leichtbau of 1992 and the Turbo S of 1995, both began as Exclusive projects. The 964 model, in particular, was the first Porsche to wear Speed Yellow, a shade devised by Sprenger and design chief Harm Lagaaij. Perhaps the last significant special order to be squeezed out of Zuffenhausen was a narrow bodied 993 turbo cabriolet, of which 14 were made for another character, Fritz Haberl, the Munich car dealer. ‘Exclusive’ would become the purveyor of individual colour schemes, special wheels and cabin fittings that it is today. “It’s still a very lucrative business,” confides its creator.

Rolf Sprenger retired from Porsche in 2006. Since then he has established himself as a specialist in used Porsches: “I do inspections for clients and advise on restoration costs and which companies to use. For some clients, I manage their entire restoration project. Occasionally I handle a Mercedes 300SL or an old BMW, but it’s mostly Porsches of course,” he adds.

Friendly with Wolfgang Porsche for many years, Sprenger also has the rather enviable job of looking after der Wolfi’s private collection, housed at the family’s Austrian home at Zell am See. And if that is not enough for a man nearing his ninth decade, he will also arrange FIA passes so that you can compete with your historic Porsche in ADAC events. In fact, he can do most things, but he still would not offer to put a swimming pool in your caravan.
Written by: Kieron Fennelly
Images by: Porsche Werkfoto and Virtual Motorpix/Glen Smale
Hopeful that people like Rolf Spenger are allowed to exploit their talents. Perhaps a proof that automobile engineering has a vitalising effect. (I shaal celebrate my 84th birthday in a few weeks…)
I was just told that Rolf Sprenger died this weekend (end of February 2021). Very sad.
Christoph you are right, I have just checked with our friend at the Museum, and he has just confirmed this. He didn’t know any details, but they will be issuing a press release shortly. I will do an obituary piece on him next week as I have interviewed him several times and I have photos of him from my visits, so that will happen next week. But this comes as a shock as he was apparently healthy up until recently. Thanks for alerting me!!