Believed in proving the speed and durability of his automobiles in competition.  During the decade of the twenties, his automobiles won the Indianapolis 500 in 1924, 1925, and 1927, while finishing second or third in four of the other seven Indianapolis events.  A Duesenberg was the first 500 mile race winning car to average better than 100 miles per hour, in the hands of Peter DePaolo in 1925.  Tommy Milton drove a Duesenberg to a land speed record of 156.046 miles per hour for the measured-mile at Daytona Beach in 1920, and Jimmy Murphy drove a Duesenberg to victory in the 1921 French Grand Prix.  During World War I, Duesenberg and his brother Auggie produced a variety of aircraft engines for military use including manufacture of the famous U-16 Bugatti.  Established in 1917 in Indianapolis the Duesenberg Motor Corporation developed a line of high-grade classic American passenger cars, the first to use an eight-cylinder in-line engine.