Amazing Innovations: Disc Brakes

January 27, 2014
Story By
Evan Griffey

For as long as cars have been made to "go" they've also needed to "stop". In an effort to overcome Fred Flinestone's way of braking, cars - especially race cars - have evolved in their manner of braking throughout the decades. It was at the 1953 24 Hours de Le Mans that, in my eyes, the first successful use of discs brakes occurred within Jaguar's dominating C-Type racers. The Leaping Cats put a proper thrashing on the big names of the day - finishing first, second, and fourth. The Dunlop four-disc set-up was able to tame the two biggest problems facing disc brakes of the era; boiling brake fluid and throwing pads - where the braking material separates from the backing plate in an immediate, untidy, and dangerous manner. Like all proper race cars, the C-Types were thin-skinned and lightweight but they were still being out-muscled by the likes of Ferrari, Alfa Romeo, and Lancia, not to mention the American V8-powered Allards. The C-Type was powered by a 220 horsepower inline 6 while the Ferrari contingent had double the cylinders and 375 ponies under their hoods. The innovative binders did not provide a significant advantage in all-out stopping power compared to the competition’s drum set-ups but it was their ability to endure the extreme heat cycling of repeated use on the track that won the day for Team Jaguar. In a race built on endurance, they absorbed the abuse all the way to the winner’s circle.

Winning drivers Duncan Hamilton and Tony Rolt set many records in their victory at Le Mans (first over 100 mph average speed, first over 4,000 kilometers traveled, and first to complete more than 300 laps) …and the innovation that is disc brakes never looked back.

After Jaguar’s antics on the track, disc brakes were primed for production car use. But what constitutes a production car? Here’s the lowdown you can call the shot at the end... Rewind to the brass car era. The first application of a disc-and-caliper design was pulled off in England in 1902 by Lanchester, but this set-up featured cable actuation and was quite problematic in that it lacked what we call stopping power.

Fast-forward to 1949 and look to the Hoosier state. Indiana-based Crosley produced the first production car with traditional disc brakes. The Crosley (pictured top) featured a Goodyear/Hawley system but this set-up came up a tad short in the success category. The calipers employed on the system were taken from the airplane industry and were unable to meet the demands of the repeated use seen on the road. It should be noted that the 1948 Tucker had disc brakes in the plans, but cost and time constraints kept them off the final product.

In 1955 Austin Healey equipped its 100S with discs at the corners, but purist will point out that the car was A) limited in its production, and B) ‘built for competition.’ Enter Jensen and its 541 sports car in late 1956. It had traditional disc brakes and was a straight shooting road car. Case closed… not so fast… The production run for the Jensen was a scant 53 units. The French will argue it has gotten the short end as its candidate, the Citroen DS, sported modern discs in late 1955. But naysayers will want to argue when does a car go into ‘production?’ The DS debuted at the Paris Salon in October of ‘55 and only 69 were built at year’s end. Yikes! Got a headache yet?… Let’s stick with the Jag!

Amazing Innovations: Disc Brakes

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