In 1924, Vittorio Jano created his first straight-eight-cylinder engine for Alfa Romeo, the 1987 cc P2, with common crankcase and four plated-steel two-cylinder blocks, which won the first World Championship ever in 1925. Although it was a straight-8, the 8C designation was not used. As far as production cars are concerned, the 8C engine powered two models, the 8C 2300 (1931–1935) and the even more rare and expensive 8C 2900 (1936–1941), bore increased to 68 mm and stroke to 100 mm .
The first model was the 1931 ‘8C 2300’, a reference to the car’s 2.3 L (2336 cc) engine, initially designed as a racing car, but actually produced in 188 units also for road use. While the racing version of the 8C 2300 Spider, driven by Tazio Nuvolari won the 1931 and 1932 Targa Florio race in Sicily, the 1931 Italian Grand Prix victory at Monza gave the “Monza” name to the twin seater GP car, a shortened version of the Spider. The Alfa Romeo factory often added the name of events won to the name of a car.
Initially, Alfa Romeo announced that the 8C was not to be sold to private owners, but by autumn 1931 Alfa sold it as a rolling chassis in Lungo (long) or Corto (short) form with prices starting at over £1000. The chassis were fitted with bodies from a selection of Italian coach-builders (Carrozzeria) such as Zagato, Carrozzeria Touring, Carrozzeria Castagna, Pininfarina and Brianza, even though Alfa Romeo did make bodies.
Some chassis were clothed by coach-builders such as Graber, Worblaufen and Tuscher of Switzerland and Figoni of France. Alfa Romeo also had a practice of rebodying cars for clients, and some racing vehicles were sold rebodied as road vehicles. Some of the famous first owners include Baroness Maud Thyssen of the Thyssen family, the owner of the aircraft and now scooter company Piaggio Andrea Piaggio, Raymond Sommer, and Tazio Nuvolari.