Bourke engine

 The Bourke Engine was designed by Russell Bourke in the 1920s, as an improved two-stroke engine, based around detonation combustion instead of using the more progressive burn normally found in Otto Cycle engines. Despite finishing his design and building several working engines, the onset of World War II, lack of test results, the poor health of his wife and investors moth-balling further developments in 1958 compounded to prevent his engine from ever coming successfully to market. The main claimed virtues of the design are that it has only two moving parts, is light weight, powerful, has two power pulses per revolution, and does not need oil mixed into the fuel.

The Wave Disk Generator also employs high temperature shock wave fuel detonation instead of lower temperature progressive burn.