Uploaded February 2026 | Updated September 2026, 2 weeks ago

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There have been many engine valve designs since the dawn of the internal combustion engine. What made poppet valves stick? (See what we did?) There were many other designs and some, like the sleeve valve in the Bristol Centaurus WWII radial aircraft engine, that worked very well. Classic Kevin Cameron stuff here as he and Mark Hoyer discuss the relative merits of engine valve types.

In this video, Kevin referred to this website about unusual engines. The website's parent name is the Museum of RetroTechnology. There is quite a volume of unusual engines and information on this page alone, never mind the rest of the site: douglas-self.com/MUSEUM/POWER/unusualICeng/unusualICeng.htm

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