In 1926, Alfa Romeo’s Chief Engineer, Vittorio Jano, set to work on a touring car that was centered around the brand-new overhead-cam, 1.5-liter, inline six-cylinder engine.

The 6C 1500 officially entered production in 1927, and the Sport version, which became available a year later, featured a twin overhead cam that raised output by 10 to a brisk 54 horsepower.

In 1929, the 6C 1500 Super Sport was introduced, and it featured two-seat spider coachwork and an optional Roots supercharger, which increased maximum power to 76.

For the 1929 model year, Alfa Romeo bumped up engine displacement to 1,750 cubic centimeters, and the resulting 6C 1750 was produced in four more series of gradual improvements over the following six years.

The model quickly proved to be one of Alfa’s most popular, and expensive, creations.

Nearly 2,600 left the Portobello factory through 1933, each one tabbed at a price hovering around 50,000 lire—an incredible cost considering that most orders left the factory...