MONTEREY, Calif.—Few car brands have managed to stake out the kind of mindshare occupied by Porsche. Celebrating its 75th anniversary this year, the company just held its seventh Rennsport Reunion, a car show crossed with a race meet at the Laguna Seca racetrack in Northern California. It drew a crowd of more than 90,000 Porschephiles at the end of September.
From its start in the aftermath of World War II, Porsche has concentrated on using clever engineering to make cars for people who like to drive. Much of that clever engineering was first proven at the racetrack before making the jump to something a bit more road-legal. And almost all of it was on display at Rennsport Reunion, from early engines with twin spark plugs and early experiments with aerodynamics through turbocharging, hybrids, and now extremely high-performance EVs.
The early days
The first Porsche-designed racing cars predate the family firm and date back to 1934 and the fearsome Auto Union V16. But the first factory-built Porsche racing car took five years to follow the company’s first road car, which appeared in 1948. When Porsche started building 356s, customers started racing them in sprints, hill climbs, and long-distance races, complete with pleas to the factory to see if it couldn’t deliver a little more power, particularly from American owners.
Porsche-engined specials built by Walter Glöcker raced in Europe and the US in 1951 and 1952 with some success, but it wasn’t until 1953 that the first Porsche 550 took a race start, in this case at the Eifel Races at the Nürburgring that May. It won its first time out. A second car was ready for Le Mans that June—a coupe like the first—and the pair finished first and second in their class, for cars with engine capacities of 1.5 L or less.
About that engine: It was located between the cockpit and the rear axle like that first 356 prototype, but unlike all the subsequent 356s—which were rear-, not mid-engined—this was preferable for weight distribution and handling.
The 356 used a modified Volkswagen air-cooled flat-four with pushrod valves, and these were also used in early 550s. But in 1953, Porsche commissioned a new engine for the 550, and designer Ernst Fuhrmann went a bit more radical. With a capacity almost exactly at 1.5 L (1.498 to be accurate), it had a larger bore and shorter stroke than the pushrod engine, or indeed most engines of the time. Ferrari also favored this oversquare approach, which took another 20 years or so to catch on with everyone else.
Instead of pushrod-operated valves, Fuhrmann opted for a complex arrangement of shaft-driven cams, two for each cylinder bank. And there were two spark plugs per cylinder, mounted in the sides of the combustion chamber rather than using a single one in the center. Aspects of this Type 547 engine would go on to inform future Porsche engines, although sometimes with some lag—Porsche didn’t introduce twin spark plugs in a road car engine until 1988.
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