Fans of the Dakar Rally (formerly the Paris-Dakar Rally) will likely recognize Tatra as a manufacturer of heavy-duty trucks, which posted an impressive six wins and five additional podium finishes in the grueling event from 1988 to 2001 at the hands of driver Karl Loprais. Long before the company was constructing race-winning trucks, however, it was producing some of the world’s most innovative automobiles, including the very first serially produced streamlined car equipped with an air-cooled and rear-mounted engine, the Tatra 77.
Introduced in March of 1934, the Tatra 77 followed the aerodynamic design ethos of the 1933 Tatra V 570 prototype, but stretched its proportions to include seating for six. It was positioned atop Tatra’s model range, far better appointed than the V 570 would have been, and the decision to produce the larger model sealed the fate of the V 570; it would remain a prototype only, though it would also influence the design of the Tatra 97.
The significantly larger Tatra 77 sported a body designed by Paul Jaray, under the watch of Tatra’s chief designer Hans Ledwinka. Jaray’s background included time with German airship manufacturer Luftschiffbau Zeppelin (LZ), so the designer was well aware of the importance of aerodynamics; producing a shape slippery to the wind would yield an automobile with superior performance, fuel economy and even reduced cabin noise. Calling on relationships established during his LZ days, Jaray was able to test his automotive designs in the airship manufacturer’s wind tunnel, and as a result the Tatra T77′s body boasted a drag coefficient of just 0.21, at least when tested in 1/5 scale.
Its body was hardly the only thing revolutionary about the T77. Using an engine mounted in the rear gave passengers a surprising amount of legroom, as the traditional center tunnel needed to accommodate a transmission and driveshaft could be eliminated. Passengers also sat low in the T77, dropping the car’s center of gravity to improve handling, at least compared to more conventional automotive designs of the day. As with the McLaren F1 supercar, introduced in 1992, early Tatra 77 models positioned the driver in the center of the car, which improved both outward visibility and weight distribution. Later T77 models were constructed in right-hand-drive, as Czechoslovakians drove on the left-hand side of the road at the time. The later T87 would become the first variant to offer both right-hand and left-hand drive.
Power for the T77 originally came from a 59hp air-cooled 2,968cc V-8 engine, which gave the large sedan a top speed of 87 MPH. Just 105 examples of the T77 were constructed before the automaker moved on to the T77a in 1935, which bumped displacement of the air-cooled V-8 to 3,377cc and output to 75 horsepower. That produced a new top speed of 93 MPH, but the T77a’s twitchy handling (the result of a long wheelbase and an extreme rear weight bias) likely scared off potential buyers. Visually, the most notable difference between the T77 and the T77a was the latter model’s central headlight, which could be ordered to turn with steering wheel, allowing drivers to see deeper into a corner.
Underneath, both the T77 and the T77a featured a four-wheel independent suspension, using swing axles in the rear and a transverse leaf spring setup in the front. While the T77 was a large car, with a wheelbase of 124 inches and an overall length of nearly 213 inches (in T77a configuration), steps were taken to reduce weight wherever possible. A magnesium alloy called Elektron was used for the engine’s crank case, as well as for the transmission casing, and the overall weight of the T77 came in at under 1,800 kilograms (3,960 pounds).
In 1936, Tatra debuted a new variant of the T77a, this time called the T87. Like its predecessor, the T87 sported an aerodynamic skin (though with a higher drag coefficient of 0.244, when tested in an identical fashion to the T77) and carried on the earlier cars’ tradition of mounting an air-cooled V-8 engine behind the rear axle. To save weight and improve the car’s handling, some 12 inches were removed from the T87′s wheelbase and its V-8 engine was cast from a lightweight alloy. As a result, the T87 tipped the scales 400 kilograms (880 pounds) lighter than its predecessor, which quickly gave the car a reputation for superior speed and handling.
The T87′s air-cooled V-8 now featured an overhead-camshaft design, and though displacement was cut back to the original 2,968cc, output remained at 75 horsepower. As a result, the T87 now achieved a top speed of 100 MPH, making it among the fastest cars in its class despite its diminutive V-8 engine. Production of the T87 would continue until 1950, remarkably including the years clouded by World War II. Favored by German officers for its composed ride and handling, Tatra was allowed to produce the T87 throughout the war years, officially for “civilian” consumption, though such transactions would likely have been rare occurrences.
Text from Hemmings
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