In the first third of the 20th century, car manufacturers were in a real race: to produce the fastest cars they could. Renault already had some commercial success with the 40CV, production of which began in 1911, However, it was the replacement of the older six-cylinder 7.5-litre engine with a larger 9.1-litre version in the Type HD Version of 1920 that really made a difference, followed by the addition in 1922 of a hydraulic servo-brake system. When Renault then streamlined the 40CV in 1925 and 1926, the records began to tumble fast.