PROVENANCE
Porsche AG, Stuttgart, Germany (retained for works team in 1974)
Vasek Polak, Hermosa Beach, California (acquired from the above in 1975)
Jeff Lewis, Newport Beach, California (acquired from the above in 1998)
Gregory Galdi, Hauppauge, New York (acquired from the above in 2002)
John Kotts, Houston, Texas (acquired from the above in 2007)
Current Owner (acquired from the above in 2010)

RACE HISTORY
24 Hours of Le Mans, June 1974, Müller and van Lennep, No. 22 (2nd Overall)
6 Hours of Watkins Glen, July 1974, Müller and van Lennep, No. 9 (2nd Overall)
1000 Km of Le Castellet, August 1974, Müller and van Lennep, No. 14 (7th Overall)
1000 Km of Brands Hatch, September 1974, Müller and van Lennep, No. 5 (5th Overall)
24 Hours of Daytona, February 1977, Ongais, Follmer, Field, No. 00 (DNF)
3 Hours of Mid-Ohio, August 1977, Follmer and Holmes, No. 16 (26th Overall)

EXHIBITED
Monterey Historic Automobile Races at Laguna Seca, Monterey, California, August 1998
Rennsport Reunion III, Daytona Beach, Florida, November 2007
Classics at the Castle Porsche Concours, Essex, UK, September 2010
Amelia Island Concours d’Elegance, Amelia Island, Florida, March 2013
Louwman Museum, “Martini Racing” Exhibit, The Hague, Netherlands, February–May 2014
Hampton Court Palace Concours of Elegance, Surrey, UK, September 2014

LITERATURE
Jürgen Barth and Gustav Büsing, The Porsche Book: Porsche Race Cars, model discussed on pp. 227–234
Dominique Pascal, Porsches at Le Mans, pictured and discussed on p. 62
John Starkey, From R to GT2: The Racing Porsches 911 & 930, pictured and discussed on pp. 428–449
Total 911, issue 128, “Porsche 911 Carrera RSR Turbo 2.1: The First Monster”

THIS CAR
At the Frankfurt Motor Show in September 1973, Porsche unveiled a special 911 concept that would change the course of sports car history. Featuring wide fender flares, a large rear wing, and the word “Turbo” emblazoned over its haunches, the new car offered an exciting glimpse at the future of the 911.

A month later, Porsche announced that it would be entering an all-new turbocharged Carrera RSR in the FIA’s Group 5 category for the 1974 World Championship for Makes. Similar to the RSRs campaigned during the 1973 season, these new cars were to be entered exclusively by the Porsche factory team and sponsored by the Martini & Rossi beverage company.

At the time of the announcement, Porsche had only just begun to develop a turbocharged racing 911, yet the project was encouraging for several reasons. Not only would a turbocharged model expand on the technical expertise gained during the final years of the 917 program, it would set the stage for a top-of-the-line 911 Turbo production model. Furthermore, the promise of a “silhouette formula” in the near future made a Group 5 Turbo Carrera an ideal platform for experimentation.

Over the winter of 1973–1974, Porsche began work on its latest racing 911, using the previous year’s RSR as the foundation.

To comply with FIA regulations, which limited capacity to three liters, a 2.14-liter, turbocharged flat-six engine was developed. This engine utilized a magnesium crankcase, polished-titanium connecting rods, large-capacity oil pumps, a twin-plug ignition, Bosch mechanical fuel injection, and sodium-cooled valves. At the rear of the engine, a single KKK turbocharger was fitted, and supported by a specially fabricated aluminum cross member. This potent engine, capable of delivering over 500 bhp, was mated to a five-speed transaxle modified with an oil cooler, an 80% locking differential, and 917-type half-shafts for increased durability.

The chassis was a complete departure from the production 911, with Porsche implementing components and technology from its prototype racing cars. The torsion-bar suspension was completely replaced with boxed-aluminum trailing arms, progressive-rate titanium coil springs, Bilstein shock absorbers, and anti-roll bars. The result was a suspension assembly that was 66 lbs. lighter than the production RSR. This reworked foundation also allowed Porsche to fit center-lock 917-type wheels and massive rear tires for increased traction.

The bodywork made extensive use of fiberglass, which was used to form the fenders, doors, and deck lids. Inside, the cockpit was stripped of all unnecessary details and outfitted with a lightweight aluminum roll cage, turbo pressure gauges, and an adjustable boost knob. A 120-liter fuel tank was placed behind the seat, and the oil tank was relocated to the front of the car, thereby reducing variations in weight distribution over the course of an endurance race.

At the rear, a substantial wing increased downforce and provided a functional inlet for the intercooler. In an attempt to maintain a visual relationship with the production 911, the rear wing was painted black to deemphasize its imposing scale.

Porsche built just four examples of the RSR 2.1 Turbo for the 1974 season. These cars were all built in Werk I, Porsche’s dedicated race shop, and assigned special internal numbers: R5, R9, R12, and R13.

This car, chassis 911 460 9102, or R13, was the last of the four RSR Turbos built, and the most successful. It was campaigned by the Martini Racing Porsche System factory team in four rounds of the 1974 FIA World Championship for Makes; Martini Racing entrusted it to the lead-driver pairing of Herbert Müller and Gijs van Lennep.

R13 made its competition debut at the most famous endurance race of all, the 24 Hours of Le Mans, held in June 1974. The Porsche works team also entered another RSR Turbo, R12, and they were supported by a variety of privately entered cars, including several Carrera RSRs, three 908s, and a 910. Both R12 and R13 were Group 5 entries, pitted against three-liter sports racing prototypes from Ferrari, Matra, and Mirage-Ford.

When engine troubles forced R12 to retire, R13 appeared to be Porsche’s only hope for a successful finish. Remarkably, Müller and van Lennep had the car running in 2nd Place in the early morning hours. Around 10 a.m., the RSR Turbo lost fifth gear, causing the team to lose 40 seconds on each lap to the leading Matra. Just before 11 a.m., the Matra suffered its own gearbox issues; however, this was quickly (and somewhat ironically) resolved by Porsche, which supplied gearboxes to the French team.

By the time the Matra returned to the track, it had lost 45 minutes, and R13 was now on the same lap. The Porsche, missing top gear on the high-speed course, was no match for the Matra’s pace. It finished the race in 2nd Place, an extraordinary result given that the RSR Turbo was an experimental project, recently developed from a production GT car. Had it not encountered a gearbox problem late in the race, R13 might have been the overall winner at Le Mans in 1974.

Following its successful debut, R13 was shipped to the US, where it took part in the 6 Hours of Watkins Glen. Once again driven by van Lennep and Müller, it placed 2nd Overall, beaten only by a factory-entered Matra.

After Watkins Glen, R13 returned to Europe and finished out the 1974 season with a 7th Place finish at Le Castellet in August and a 5th Place at Brands Hatch in September. At the end of the season, Porsche ranked third behind Matra and Mirage-Ford in the World Championship for Makes. This was hailed as a remarkable achievement and proved to Porsche that a turbocharged 911 racing car could compete with the world’s most advanced machinery.

Following the 1974 season, Porsche sold R13 to influential California dealer and race team owner Vasek Polak. Although the RSR Turbo was not raced during the earliest years of Mr. Polak’s ownership, in 1977 he agreed to rent the car to Ted Field’s Interscope Racing team for the 24 Hours of Daytona. For this outing, a temporary Fablon wrap covered most of the original Martini & Rossi livery, and the car wore Field’s preferred racing number – 00. Driven by Danny Ongais, George Follmer, and Field himself, R13 qualified in 6th position, but engine problems forced an early retirement.

In August 1977, the 2.1 Turbo was loaned to Follmer for the 3 Hours of Mid-Ohio. In a race dominated by Porsche’s new 935s, R13 was driven by Follmer and Howdy Holmes to 26th Overall. Following these final outings in 1977, R13 returned to California and remained a fixture in Vasek Polak’s private collection, seeing very little use over the next two decades.

After Mr. Polak’s death, R13 was sold in 1998 to Jeff Lewis of Newport Beach, California, a Porsche collector who owned many significant cars, from a very original 3.0 RSR to a Le Mans-winning 956. After being mechanically sorted, the RSR Turbo was exhibited at the Monterey Historic Automobile Races at Laguna Seca in August 1998, where Porsche was the featured marque.

R13 remained in Mr. Lewis’ collection until 2002, when it was sold to New York collector Gregory Galdi. Five years later, the RSR Turbo was sold to John Kotts, a Texas-based collector who built an exceptional stable of historically significant Porsche racing cars, including the first 935 and a works RS60.

During Mr. Kotts’ ownership, the RSR Turbo received further mechanical attention, including an engine rebuild by Porsche specialist Graham Everett. In 2007, R13 was displayed at Rennsport Reunion III, held at the Daytona International Speedway in Florida, where it had been raced three decades earlier by the Interscope team.

Since 2010, the consignor has maintained R13 in his impressive stable of endurance racers and exhibited this important car at many top events, from the Classics at the Castle Porsche Concours to the Amelia Island Concours d’Elegance. Unlike many historic racing cars, R13 was retired early and spared from an active career in vintage racing. It has been preserved by knowledgeable collectors and carefully maintained by Porsche specialists. As a result, this RSR Turbo remains in exceptional unrestore