Automobiles were still in their relative infancy in 1905, but they had been growing more popular for years. There was a problem, though: they were extremely noisy. One cause of the noise were the ...

This file type includes high resolution graphics and schematics when applicable. The images above are simple cross sections of a typical spool valve (left) and a poppet valve (right). (Courtesy of ...

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 ...