too. After an increase in sales, the existing facilities were too small, so in 1910 the factory moved to a new facility at 138 Boulevard de Verdun, Courbevoie. The following year saw the creation of advanced bodywork. By 1912, 350 workers were producing over 1000 cars annually, and offered four- and six-cylinder sidevalve engines. During the First World War, Delage produced munitions. Production of passenger cars virtually stopped, with the exception of some fabrication for the Army. But the Delage factories were running full support for the war effort. When the war concluded, Delage moved away from small cars and made its reputation with larger cars. First up was the CO, with a () fixed-head sidevalve six producing 20 hp. The CO plans had been drawn up during the conflict; this was the first passenger car with front brakes. It was joined by the DO with a 3-liter four. The 1920s were really the first "Golden Age" of Delage. The most famous were the DE and DI: 4 cylinders of about 2 liters and 11 hp. Delage also attempted to compete with Hispano-Suiza, with the GL of 30 hp and 5954 cc, with some success. After that came a new generation of six-cylinder cars, like the MD (3174 cc) and DR (2516 cc), the best-selling vehicle in the history of the brand, designed by engineer Gaultier. Both the CO and DO were replaced in 1922. The CO became the CO2, which changed to an overhead valve twin-plug head, producing , while the DO was supplanted by the DE with a () sidevalve four and, unusual in a production car even in this era, four-wheel brakes. The CO2 completed the Paris-Nice run in 16 hours, an average of . The next year, the new DI also switched to OHV with a () four, fitted with magneto ignition and thermosyphon cooling; all had four-speed gearboxes and Zenith carburettors. At the other end of the scale, the GL (Grand Luxe), also known as the 40/50, replaced the CO2, being fitted with a magneto-fired () overhead cam six. In 1923, a hillclimb car with DI chassis, larger wheels and tires, and () CO block (with three Zenith carburetors) was produced. Delage scored successes at La Turbie and Mont Ventoux. This car was joined by a () V12, which broke the course record at the Gaillon hillclimb, with Thomas at the wheel. Thomas would set