In 1920, Ferdinand Porsche developed the first-class car “AD-617” with a 6-cylinder engine with a displacement of 4.4 liters, made of light alloys. The experience gained made it possible in 1923 to produce the passenger model “10/50 HP” or “ADM-1”, capable of reaching a maximum speed of 100 km / h. Her engine had one carburetor and one overhead camshaft. The “ADM-2” model with two carburetors was produced in 1925-1927, and the “ADM-3” with a 3-liter engine appeared to replace in 1926. Their sports performances had a shortened chassis and for the first time (among branded cars) exceeded the speed of 160 km / h.
In 1927, designer Karl Rabe prepared a new long-base model “ADR”. It was distinguished by a central tube frame with cantilever crossbars and a rear independent suspension in a combination of three springs with swinging drive axles (with front dependent suspension). All springs had progressive stiffness and provided high comfort at full load and at high speed. 70 hp engine relied on the front fork fork frame. In short-base sports versions “12/100" the engine power was increased to 100 hp.
Two more powerful models, the “ADR-6 Bergmeister” with a 6-cylinder engine and the “ADR-8 Alpin” with an 8-cylinder engine, closed this series. At their request, it was possible to install various open or closed bodies of the best body builders in Europe. “Bergmeister” was produced until 1934 and became one of the last cars of the brand “Austro-Daimler”.