1930 Alfa Romeo 6C 1750 GS Spyder

Powered by a supercharged 1.75-liter twin-cam engine, the Alfa Romeo 6C 1750s won its class in most races. The Zagato Spider coachwork is as elegant as it is functional.

Alfa Romeo's Chief Engineer, Vittorio Jano, began work on a touring car in 1926 on a 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, came with a twin overhead cam that boosted output by 10 to a brisk 54 horsepower. The 6C 1500 Super Sport followed in 1929, featuring two-seat spider coachwork and an optional Roots supercharger, which increased maximum power to 76.

Alfa Romeo increased engine displacement to 1,750cc in 1929, and the resulting 6C 1750 was produced in four more series of gradual improvements over the following six years. Nearly 2,600 examples left the Portobello factory through 1933, and most examples left the factory with any mounted bodywork. Most examples of the 6C 1750 series were equipped as the single-cam 'Turismo' version; a few were classified as a 'Sport' version, which were built on a 114-inch chassis and equipped with the twin-cam engine. The majority of the Sport examples wore ALfa saloon coachwork and were soon renamed 'Gran Turismo.' The Zagato-bodied Super Sport examples rested on an even-shorter 108-inch wheelbase platform and were available with finned alloy superchargers and intake manifolds.

In 1930, the Super Sport name was updated to Gran Sport. Styling revisions included a sloping radiator which gave it a rakish appearance and increased the surface area of the radiator for improved cooling. By this point in history, the 6C 1750 Gran Sport now came standard with a Roots supercharger, which developed 85 horsepower.

By Daniel Vaughan | Mar 2025