Porsche 718 RSK: the racing Spyder that succeeded the 550

The Porsche 718 is a series of one- or two-seat sports-racing cars built from 1957 to 1962. It was a development of the successful 550A with improved bodywork and suspension, and its open-wheel single-seater versions took Porsche into Formula Two and Formula One.

Porsche 718 at a glance

History of the Porsche 718

The 718 grew directly out of the 550A. It kept the mid-engined layout and the 142 hp 1.5-litre Type 547/3 quad-cam Fuhrmann engine, and gained revised bodywork and suspension. The full name was 718 RSK, where RS stands for RennSport and the K refers to the shape of the revised torsion-bar suspension. It raced first at the 1957 24 Hours of Le Mans, where Umberto Maglioli and Edgar Barth retired after an accident.

The results came in 1958: the RSK Spyder number 29, with a 1.6-litre engine, finished third overall at Le Mans in the hands of Jean Behra and Hans Herrmann, and the 1.5-litre car number 31 of Edgar Barth and Paul Frère came fourth overall and first in class. Behra also finished second at the Targa Florio. In 1959 Barth and Wolfgang Seidel won the Targa Florio outright, the type’s first overall victory there, and a 718 took the European Hill Climb Championship in both 1958 and 1959.

Formula racing was the next step. In 1957 the FIA allowed cars with enveloping bodywork into Formula Two, and for 1958 Porsche fielded a modified 718 called the RSK Mittellenker, with the single seat moved to the centre of the cockpit and the steering wheel, pedals and gear lever relocated to suit. Jean Behra won the F2 event at Reims in it, Edgar Barth was sixth overall and second in class at the 1958 German Grand Prix, and Masten Gregory won both his heat and the F2 class at the 1958 Berlin Grand Prix on the AVUS.

In 1959 came the 718/2, an open-wheel monoposto that married the 718’s mechanicals to a narrow single-seat body. Wolfgang von Trips qualified twelfth at Monaco and crashed on the second lap; Jo Bonnier finished third at Reims. For 1960 the production 718/2 received revised bodywork, a six-speed transaxle and a wheelbase 100 mm longer, and five cars were built. When the FIA limited Formula One engines to 1.5 litres from 1961, Porsche could use the 718/2 almost unchanged in F1.

The sports car continued to develop. The RS 60 of 1960 answered new rules on windscreens and cockpit size and added an optional 1.6-litre engine with 160 hp and a new double-wishbone rear suspension; it gave Porsche a 1–2 at the 1960 12 Hours of Sebring, the company’s first overall win in a World Sportscar Championship race away from the Targa Florio, and it won the Targa Florio again. The RS 61 of 1961 was almost identical and won the European Hill Climb Championship. The W-RS of 1961 later received a 2.0-litre flat-eight Type 771 with 240 hp and finished eighth at Le Mans in 1963, and the 718 GTR Coupé took the Targa Florio in 1963 before the 904 replaced the line in 1964.

Design and features

• Four-cam Fuhrmann engine: the same 547/3 unit that had made the 550A fast, here with 142 hp.
• Centre-steer option: the Mittellenker moved the driver to the middle of the cockpit for Formula Two.
• Monoposto 718/2: an open-wheel body on the same mechanicals, used in Formula Two and Formula One.
• Hill climb dominance: the type won the European Hill Climb Championship repeatedly, a run Porsche kept up until 1982.

Porsche 718 versions

• 718 RSK (1957–1959): the original sports-racing Spyder.
• 718 RSK Mittellenker (1958): centre-steer car for Formula Two.
• 718/2 (1959–1960): open-wheel monoposto, five built.
• RS 60 (1960): 1.6-litre engine option, double-wishbone rear suspension, Sebring 1–2.
• RS 61 (1961): almost identical to the RS 60.
• W-RS and 718 GTR Coupé: flat-eight developments that raced into 1963–1964.

The 718 replaced the Porsche 550 and was itself replaced by the Porsche 904. More cars are in the Porsche collection.

Sources

• Porsche 718, English Wikipedia: versions, engines, racing record