After the war Alsace became French and so did the marque Bugatti. On returning to Molsheim the camshafts were exhumed and a team of Bugatti racing cars was ready for action by 1920. On their first outing they entered 3 cars for the Coupe des Voiturettes at Le Mans which Friderich won. The following year he won the Italian Voiturette Grand Prix at Brescia and his team mates took the next three places. From then the Type 13 was always known as the "Brescia" Bugatti.

The production cars were the Type 22 with the short chassis and the 16-valve ball bearing engine and the Type 23 with the plain bearing engine, both giving about 40bhp, in a longer chassis and called the "Brescia Modifie". These were popular little cars and continued to be made up to 1926, by which time about 2,000 had been sold. They were popular with amateur racing drivers, and two short chassis 16-valve cars, named "Cordon Rouge" and "Cordon Bleu", were successfully raced by Raymond Mays with sponsorship from Mumm the famous Champagne house.

Ettore Bugatti had experimented, in 1911, with an 8-cylinder car using two Type 13 engines mounted in tandem and had also designed a straight 8 aero engine during the war. The logical development of this was the 3-litre straight-8 Type 28 with rear transaxle, which was displayed, unfinished, at the Paris Salon and London Motor Show in 1921. It never went into production due to lack of funds, but it was eventually completed.

In 1922 came the Type 30 with a 2-litre engine and the gearbox in the more usual position.

The engine was made with two cast iron, fixed head, cylinder blocks, mounted one behind the other, on a common aluminium crankcase. They had a single overhead camshaft, operating 3-valves per cylinder, housed in an aluminium case which tied the cylinder blocks together at the top. It was initially built as a racing car and the first four cars, with bulbous radiator cowls, were entered for the French Grand Prix at Strasbourg, where second place was taken by De Viscaya. They were less successful at the, new, banked Monza track for the Italian Grand Prix due to unsuitable gearing for this very fast circuit and broke a connecting rod at Indianapolis.

In 1923 the French Grand Prix was run at Tours and the Type 30s were entered with Bugatti built streamlined bodies nicknamed "tanks" because of their unusual appearance. The engines were fitted with composite crankshafts which had roller bearings for the main and big ends fed by splash lubrication to grooves in the circular crank webs. There was an early type of hydraulic braking on the front wheels, but this proved unreliable and was abandoned.

Friderich did well to finish 3^rd but the greatest interest was shown in the supercharged Fiats which gave a pointer towards future development.

The road going Type 30 was expensive but sold surprisingly well, about 600 being made up to the end of 1925. When new it received considerable acclaim from the motoring press which was in later years more critical when comparing it, somewhat unfairly, to later models. The experimental Type 33, with rear transaxle, harking back to the Type 28 was not put into production and so the Type 38 replaced the Type 30 in January 1926. The 2-litre engine, even when supercharged, did not give sufficient power for a marque with a reputation built on performance and so after 385 were made it was replaced by the Type 44 in 1927. The engine was enlarged to 2,991cc and gave about 80bhp (a modest increase on the 70bhp of the Type 38), but with more torque it made for a much improved touring car. Although supplied in chassis form to many coachbuilders there was by this date a fully operational bodyshop at Molsheim. The Type 44 proved to be a popular car and nearly 1,100 were sold making it the most numerous Bugatti model.

The development of the racing cars had continued and in 1924 the most famous Bugatti of all, the Type 35, made it's debut at the French Grand Prix held that year at Lyon. This was a completely new design with the engine giving about 90bhp and the fully roller bearing crankshaft now running on 5 main bearings. The chassis was also new and was very slender at the front,deep in the centre and finished behind the rear axle but with forward facing quarter elliptic springs. The hollow tubular front axle was a work of art with the springs being fed through it. The wheels caused a sensation, being cast in aluminium and incorporating the integral brake drums. The whole car was very light and dainty with a most attractive 2-seat racing body and was capable of about 110 mph. The new wheels had "bolt on" detachable rims and the tyres were made especially for them, but unfortunately they had trouble with these tyres in the race and Chassagne and Friderich only managed to finish in 7^th and 8^th place.

Once the tyre problem was solved they were developed into extremely successful racing cars, in fact the most successful of all makes in the 1920s when they won more races than all the other makes put together. In 1926, for example, they won 12 major events and the Championship of the World as the manufacturer's championship was called. The 1.5-litre Type 39 was introduced in 1926 giving 80bhp.