Duesenberg Eight Speedway Roadster
The legendary Duesenberg eight-cylinder racing engine debuted at Indianapolis in 1919, and the lessons learned in competition spurred myriad ongoing improvements. Its sound basic design also allowed compliance with the mandated displacement cuts of 1920 and 1923.
For the 1923 racing season, the Duesenberg 122-cubic inch engine incorporated a gear-driven, dual overhead-camshaft head with four valves per cylinder and pent-roof combustion chambers, succeeded by simpler two-valve hemispherical combustion chambers for 1924 and later on. Based upon their prior WWI experience with aircraft engines, which also required maximum output at high and relatively constant engine speeds, the Duesenbergs turned to supercharging to increase output.
The supercharged Duesenberg was successful at Indianapolis in 1924, when Joe Boyer took the checkered flag after taking over from co-driver L.L. Corum on Lap 109. A sixth-place finish was also achieved by Peter De Paolo, who was able to convince Fred Duesenberg to give him a spare car, the only non-supercharged car of four on the team. At the end, he was the team’s only survivor aside from the winning Duesenberg of Corum and Boyer.
That strong performance earned De Paolo a supercharged factory car for the 1925 season, and with that bright yellow Duesenberg, he scored a convincing win at the 500. In the process, he also set a new average speed record at 101.13 mph, which stood for seven years.
This car was auctioned off by RM Auctions in March of 2011 at the Ritz-Carlton, Amelia Island, Florida.
225 bhp, 121.3 cu. in. supercharged DOHC inline eight-cylinder engine, three-speed manual transmission, live axle suspension with semi-elliptic leaf springs, and hydraulic rear-wheel-only drum brakes. Wheelbase: 96"
Source: RM Auctions
Photo Credit: Copyright Simon Clay