After the end of World War I, the Lawrance engineers worked with both the Army and the Navy in developing their L-1 onto a nine-cylinder radial engine, which became the 200 hp Model J-1. It was the best American air-cooled engine at the time and passed its 50-hour test in 1922.
The U.S. Navy badly needed light, reliable engines for its carrierborne aircraft. As a means of pressuring Wright and other companies into developing radial engines, it gave a contract to Lawrance for 200 of the J-1 radial and ceased buying the liquid-cooled Wright-Hispano engines. At the urging of the Army and Navy the Wright Aeronautical Corporation bought the Lawrance Company, and subsequent engines were known as Wright radials. The Wright Whirlwind had essentially the same lower end (crankcase, cam, and crankshaft) as the J-1.