1933 BMW 3/20 PS AM 4 Sedan
Marking a critical transition for the Bavarian manufacturer, this sedan represented BMW’s first completely independent automotive design after moving beyond its earlier collaboration with the Austin Motor Company.
The 3/20 PS was manufactured from 1932 to 1934, replacing the licensed Austin 7-based 3/15 model and establishing BMW’s reputation for engineering innovation.
Advanced for its time, the 3/20 featured independent suspension at all four corners with a swing-axle rear setup that provided superior handling compared to conventional solid axles. The 782cc four-cylinder engine incorporated overhead valves and a water pump, producing 20 horsepower (a significant improvement over its predecessor’s side-valve design).
The AM 4 designation indicated “Ausführung München” (Munich Version) and represented the final development stage, distinguished by its new four-speed gearbox.
Built on an 85-inch wheelbase with bodies primarily constructed by Ambi-Budd in Berlin and other independent coachbuilders, these cars established the foundation for BMW’s automotive legacy during the early 1930s.
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