Many notable innovations appeared on cars in the 1920s and 1930s.
Among these were independent suspension, greatly improving ride quality; rear engine mounting, affording better rear traction and internal packaging; air cooling of engines, removing complexity; body streamlining, reducing aerodynamic drag and thus enhancing performance and efficiency; and more equal weight distribution, making for finer and more predictable dynamics.
However, no car had embodied all of these – not until the Tatra 77.
These were combined with the backbone chassis concept of prior Tatras (wherein the need for side rails was eliminated), which had been invented by the Czech firm’s chief engineer, Hans Ledwinka, with help from his son Erich and colleague Erich Übelacker, making the 77 “different in important matters” to anything else on Earth.
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Tatra’s impressively compact and light 3.0-litre V8, attached to the backbone just aft of the rear axle, was as unusual as it looked.
It had hemispherical combustion chambers, a dry sump and overhead valves, which uniquely were opened not by pushrods but by long rockers extending from a central camshaft.
The cylinders were surrounded by a jacket, open on either side to allow the entry of external air (channelled in through louvres where the rear windscreen would usually be) and exhaust emission.
Meanwhile, the saloon body’s drag coefficient was claimed to be an incredible 0.25 (the average back then was around 0.7), thanks to the 77 being one of the first-ever cars designed using a wind tunnel.
Specifically, it was the tunnel at Zeppelin. Designer Paul Jaray was a former employee of the famous airship maker and consequently had knowledge of aerodynamics lacking within the car industry.
Even then Jaray wasn’t satisfied: when the revised 77a came in 1935, it had not only a larger-capacity V8 (3.4 litres) but also yet better aero, supposedly giving a Cd value of 0.22. Oh, and a third headlight in the centre with a moving reflector!
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