The 8C 2900 was built in two series, the 2900A and the 2900B. The 8C represented the engine size, a straight eight powerplant while the 2900 represented the size of the engine, 2905 cc. The engine was created by mounting two four-cylinder alloy blocks on a single crankcase. With the twin Roots-type superchargers attached, the 2.9-liter engine could produce between 180 hp for the 8C 2900B and 220 hp for the 8C 2900A. The suspension was all-independent with wishbones in the front and the rear had swing-axles.
The Alfa Romeo 8C 2900A was a two-seater with Grand Prix style bodywork. They were purpose-built to race and win at Italy’s famous Mille Miglia. In 1936, three examples were entered and were able to capture a first through third finish. A year later, they repeated their success again capturing the top three places. The success of the 2900A spawned the decision to create a road-going version that Alfa Romeo could supply to its customers. The 8C 2900B models were built upon two different wheelbases and had bodies that were very aerodynamic. Similar to the 2900A mechanically, the 2900B models were given a de-tuned engine that produced 40 horsepower less than the 2900A but still fast enough to be claimed the fastest production vehicle in the world with a top speed of nearly 110 mph. The Corto were short 2800mm wheelbase version while the Lungo were the long 3000 mm wheelbase versions. As was customary at the time, custom coachbuilders were often tasked with building the bodies. The 2900B had most of its coachwork handled by Touring of Italy. The vehicles could be purchased in Berlinetta, Roadster or Spyder bodies. These supercars were not only fast but they were expensive too. Since they were mechanically capable to match most vehicles on the racing circuit, many of the 2900B models were raced. Alfa Romeo constructed 13 examples of the 8C 2900B but with the 220 hp engine and most with Roadster bodies. In 1938 and in 1947, the 2900B with the 220 hp engine were able to capture the checkered flag at the Mille Miglia.
During its production lifespan, only 41 examples were produced. Three wee type 8C 2900 A with the remaining being the type B.