The origins of the Carrera engined Speedsters date back to 1954 when the Porsche competition department placed a 4-camshaft Carrera engine into a 356 coupe which had its roof lowered and had a one-piece windscreen fitted. Driven by Helmut Polensky and partnered by navigator Herbet Linge, the duo defeated Oliver Gendebien in a Lancia to win, for the second year running, the gruelling 3,197-mile Lige-Rome-Lige Rally, generally acknowledged to be the toughest rally in Europe of the period.
Porsche then decided to produce one hundred of the Type 547 Carrera engine to be placed in the 356A, the then-current road-going coupe, which would make the car eligible to take part in the up-to-1500cc GT class in World Championship races. The Carrera name comes from the Mexican road race, the Carrera Pan America, in which Porsche had done so well.
In the Auumn of 1955, Porsche experimented with seven “pre-production” Carrera Speedsters fitted with four-cam engines and other modifications. This was done in order to test the idea of a limited production run of cars that would be made available to select clients. The first of these was completed on September 14, 1955. The second “prototype” was built in November with the remaining five being built in early December.
Shortly thereafter, with lessons learned, a limited run of just eight “production” Carrera Speedsters were assembled in the final weeks of December 1955. The remaining 136 Carrera Speedsters built after January 1956 all utilized the revised 356A Speedster bodies.
Externally, the only real visual difference between this car and the regular production Speedsters was the small “Carrera” script on the sides of the front wings or fenders and another found centrally on the rear of the car.
The main difference of course, is the engine which instead of being a low horsepower “push-rod” unit, is instead one of the ultra-rare high output Type 547/1 “four-cam” units. With nearly double the horsepower and significantly more torque the cars could reach 120mph and accelerate to 60mph in 11 seconds.
This roller-bearing engine would run happily to 7500rpm, but Porsche warned customers against exceeding 6500rpm for long periods, saying that engine wear and fuel consumption increased drastically above this.
In March 1957, the Carrera Speedster of Rolf Goetze, took part in a record run at Monza. With his engine bored out to 1529cc, so that the car could run in the 1500 to 2000cc class, he and his co-drivers averaged almost 115mph for twelve hours covering one lap at 127.7mph.
The Carrera Speedster was steadily developed, primarily by lightening the car so that, by 1957, the serious racing customer could buy a car with no heater, Plexiglass windows, Weber carburetors (instead of the previously used Solex’s) and an 80-liter fuel tank to extend its range. No undercoating or soundproofing plus, the use of an aluminum Nardi steering wheel, further decreased weight. The Carrera GT’s were very successful in 1958, winning their class in almost every event they entered, including domination of SCCA E and F Production.
The real star behind the Carrera Speedster was the brilliant young engineer at the Porsche factory, Dr. Fuhrmann. The engine was very complex compared with the push-rod engines on the cutting edge of racing engine technology. It had dual ignition, four overhead camshafts large valves and aluminium pistons, cylinders and cylinder heads. The crankshaft rotated in roller bearings and the engine used dry-sump lubrication supplied by an external tank. The 1500 cc engine produced almost 110bhp, double the power of the 1500 push-rod engine.
The Porsche 356 Carrera Speedster with its special four-cam racing engine is today probably the most desirable 356 model. A fully restored Carrera Speedster will sell for around $300,000 at auction.
What the experts said:John Bolster, writing for the magazine Autosport recorded: “That 90mph third gear gave me the mastery of anything on wheels. When, on occasion, the rev-counter swung around the 7000rpm mark in top gear, the little low coupe gave a tremendous impression of sheer speed, the next obstruction suddenly seeming to fly towards one, though the powerful brakes were always able to cope.”Sports Cars Illustrated tested a Carrera GT Speedster and Jesse Alexander wrote: “It’s hard for a conventional Porsche driver to get used to the fact that the engine smoothes out at about 4200rpm, right where the pushrod Porsche would be getting rather wound up. At 5000rpm in the Carrera things start to happen, and from there on up you’ve got that feeling of being pushed in the small of the back. The acceleration is accompanied by the most unholy snarl of power you ever heard…A shattering blast of sound that sends chills up the spine of the uninitiated. The range of speeds in the gears is amazing, 40mph in first, 70 in second and 100 in third, figures hard to believe until one gets behind the wheel and experiences it.”