The 930 came into existence in perhaps one of the worst possible time periods for an auto manufacturer to debut its first supercar, yet the 911 Turbo that was still in its infancy became one of the most impactful models in the 911 lineup and one that continues to set performance standards year after year.
Beginning in October 1973, oil-producing Arab Countries and members of the Organization of Petroleum Exporting Countries (OPEC) imposed an embargo against nations that were perceived as supporting Israel during the Yom Kippur War in order to leverage their political power. The oil embargo caused tremendous turmoil in the global economy and stock market and simultaneously driving up inflation and unemployment in the affected countries. The price of crude oil quadrupled by 1974 and in addition to fuel prices reaching astronomical levels, the limited availability of gasoline led to long lines and intense rationing. The embargo crippled automobile manufactures, particularly those whose cars had been growing in size, weight, displacement, and power. The embargo on the U.S. was lifted in March of 1974, but its effects lingered for a decade. Despite all odds, Porsche was the only manufacturer to release a true supercar in this period for the U.S. market.
Porsche’s venture into turbocharging began in the early 1970s with the 917 without any intention to homologate the technology for production sports car racing or producing a turbocharged street car. The 917’s dominant streak in endurance racing was brought to a halt when pressure from competitors influenced the F.I.A. into changing its regulations for the 1972 World Championship of Makes, forcing out the 917 in the process. Porsche looked to its biggest sales market- the United States- and adjusted its focus to the premier racing series in North America, the Canadian-American Challenge Cup. However, to be competitive Porsche would have to put forth a serious effort to increase their power output to rival that of the massively powerful, big-block Chevrolet-powered McLaren M8s. If Porsche was able to drastically increase their power output, the 917/10 chassis could be their ticket to success in Can-Am competition for the 1972 season. A meeting to discuss the challenge at hand between engine designer Valentin Schäffer, Hans Mezger, Helmuth Bott, and Ferdinand Piëch considered the existing powerplant options- an existing 16-cylinder engine developing over 750 horsepower, or the reliable 12-cylinder 917 engine. Ultimately the decision was made to go with a turbocharged version of the 12-cylinder 917 engine, developed in absolute secrecy as ordered by Piëch.
Turbocharging was still considered to be an unsuitable technology to be competitive on twisting race circuits due to its inherent throttle lag and hard-to-control power delivery. Furthermore, there had yet to be a successful turbocharging package to model the new technology on, engineers were forced to learn as they went on throughout the project. One of their main challenges was how to regulate the flow of exhaust gases and manage boost pressure to provide an acceptable throttle response. The addition of the wastegate was a turning point in the development of the turbocharged 912/50 engine, and engineers continuously improved upon the system until the 850 horsepower engine reached an acceptable level of drivability. The adoption of Mark Donahue’s suggestion to replace the mechanical wastegate spring with an electric motor for the driver to adjust the boost pressure from the cockpit was just one of the many improvements made before the 917s made their debut at Mosport for their first race in June of 1972. It wasn’t long before 917s dominated Can-Am competition, taking wins in six of the nine races in the 1972 season and six of the eight races in the 1973 season.
With Schäffer and Mezger’s turbocharging package a clear success, it was clear that it was a pathway to move forward in competition for Porsche. Porsche began looking forward to Group 4 and 5 racing to employ turbocharging into their flat-six engines. Martini & Rossi partnered with the factory and provided the critical sponsorship they needed to produce a factory contender. Since the Group 5 category was effectively an open prototype class, it allowed Porsche’s race engineers a significant margin of freedom to experiment, and all of the experience and lessons learned from the turbocharged Type 912 engine was transferred to the new Carrera RSR Turbo, the car that has become known as the “Baby Turbo” by enthusiasts today. Maximum displacement for Group 5 racing was limited to 3.0 liters for naturally aspirated engines, and a 1.4 displacement handicap applied to turbocharged engines, making the maximum displacement allowed for a turbocharged engine 2.143 liters. Luckily, this displacement nearly perfectly matched one bank of the 912/50 engine, meaning that all of Porsche’s development work to match the turbochargers to the 912/50’s 4.5-liter engine could be translated into a single turbo set up on a smaller engine. On April 25, 1974, Herbert Müller and Gijs van Lennep managed a second-place overall finish in the Martini RSR Turbo despite a gearbox failure that left them with only third and fourth gears. One month later, they claimed another second-place finish overall in the 6 Hours of Watkins Glen.
Porsche’s management immediately ordered that 400 of the Typ 930 be put into production to satisfy the F.I.A.’s homologation requirements so that Porsche could enter into Group 4 competition with the new 934 Turbo RSR and deliver them into the hands of waiting privateer racers. Contrary to Porsche’s Marketing Department’s concerns about the demand for such a car, the new Turbo was met with positive praise and unexpected demand. In the period, its performance was stunning- 0-60 mph in just 6 seconds and 0-100mph in 13.1 seconds, and a top speed of 155mph put it firmly in the supercar category and in a position that no other auto manufacture at the time could rival. It was not only the fastest production car Porsche had ever produced, it was the fastest production car of any manufacturer around the globe. Its performance, matched with its 50mm wider rear fenders, 7” and 8” wide Fuchs wheels with wheel spacers, a distinctive front air dam, and whale tail spoiler gave it an exotic, aggressive appearance to match its capabilities.
RoW market Turbo first rolled off the production line to their expectant new owners in October of 1975, whereas North America received Turbo Carreras in 1976 with added emissions devices and slight exterior differences to comply with U.S. safety and emissions regulations of the time. Porsche + Audi’s marketing department attached the Carrera title to reinforce the Turbo’s status as the top of the model lineup in the United States. No matter the name, it was welcomed with open arms in the States, and a total of 1,237 Turbo Carreras were sold in its first two years of production, nearly equaling the 1,559 Turbos sold to the RoW markets.
Our sales manager Tim Kuhn and Bryan Gremchuk, one of our lead mechanics and resident 930 specialist, brought out two early 930s yesterday to compare and contrast- one a fully restored, RoW spec ’75 Turbo and the other a highly original, U.S. market ’76 Turbo Carrera for this week’s RS Insights.
For more on both cars, click the links below.
