This is probably the first purpose-built engine constructed in the United States, as well as the first double overhead camshaft engine built here.
It was built for the first Pikes Peak Hill Climb race. The engine features hemispherical-type combustion chamber design and centrally-located spark plugs (between the two overhead cams).
To our knowledge, the car with this engine was raced twice at the inaugural Pikes Peak Hill Climb. It won its class on the first run, but was not able to finish the second run for reasons unknown to us. The designer/builders of the special head on this 6-cylinder Chalmers engine were the sons of the company’s founder. There is no known connection between this engine and the Allis-Chalmers tractor manufacturer.
It is interesting to note that, while the Chalmers boys were conceiving and building this DOHC racing engine in the U.S., the Peugeot Company in France was also developing a large 4-cylinder racing DOHC engine. That Peugeot engine became the engine to beat in America during 1914-1916, and was the engine from which Harry Miller and Fred Offenhauser drew much inspiration, sparking construction of the first Miller engine in 1917.