1912 Peugeot DOHC: The Dual Overhead Cam Engine
Marc Birkigt was a Swiss engineer working for Spain's Hispano-Suiza in 1911 when he designed a 2.6-liter four-cylinder for King Alfonso XIII of Spain, with two camshafts sitting atop its cylinder head directly actuating four valves per cylinder. The engineering was so brilliant that another engineer and test driver stole the design and took it to France's Peugeot. A few months later, a near perfect copy of Birkigt's 16-valve engine powered the Peugeot DOHC to victory in the 1912 French Grand Prix. Today even your clapped-out Hyundai Elantra has a DOHC four.