This is how Porsche developed internally ventilated brake discs in 1965

Car manufacturers have always found it easier to increase the speed of their cars than to reduce it. In the 1930s, racing cars produced a lot of power but their braking performance was poor. Drum brakes, prone to overheating and inconsistent performance, were not replaced by disc brakes until the 1950s, when Jaguar, Dunlop and Sir Stirling Moss demonstrated their effectiveness on a C-Type.

Despite that leap in performance, which allowed Moss to reach an average speed of almost 160 km/h and lap the entire field at the 1952 Reims Grand Prix, disc brakes remained an imperfect solution that could not be improved until 1965. According to Porsche, although they were an improvement over drum brakes, the discs were still prone to overheating, and friction could push them above 500 °C. This could translate into a loss of effectiveness and possible accidents.

Internally ventilated disc brakes by Porsche

In 1965, however, the Stuttgart carmaker had a brilliant idea. While preparing the Porsche 906-8 Bergspyder for the renowned European Hill Climb Championship driver Gerhard Mitter, it wanted to improve the performance of its brakes. There was no doubt the 570 kg, 260 CV eight-cylinder engine would go fast, but Porsche wanted it to stop just as quickly.

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To achieve this, it developed double-walled brake discs with holes perforated between their faces. This allowed air to circulate more effectively, keeping them cooler for longer and maintaining consistent performance. The technology, installed on the front axle brakes of the Bergspyder, allowed the driver to enter corners much faster, choosing braking points with greater boldness. These new brakes were a success: a year later, in 1966, they were fitted to the Porsche 911 S. This system became the fastest technology of Porsche to reach road cars.

Today, all models from the Stuttgart brand come with ventilated brakes as standard. The German manufacturer itself has stated that “what proves its worth in motorsport should also benefit series models, and developers in Stuttgart have operated with this maxim in mind from the very beginning. The technology of the internally ventilated brake disc has been transferred faster than any previous one, and buyers of the new Porsche 911 S were able to enjoy the innovative system just one year later, in 1966. And it is now standard on all premium vehicles.”