Flat-four engine
…model through the 1920s and 1930s. The 1936 Tatra T97 pioneered the rear-engined, air-cooled flat-four, backbone chassis layout (later used by the Volkswagen Beetle), and at the same time, though unrelated, came the Steyr 50 from Austria, sporting a front boxer 4 engine with rear wheel drive. Also in 1936, English…