You've probably heard about the choke valve in your car engine's carburetor, but what does this seemingly essential component actually do?

Valve lash is adjusted mechanically at the valve stem, netting a nice, soft chatter performance buffs love to hear in a high-performance engine. Valve lash clearances are typically around 0.010 ...

This article was originally published with the title “ Improved Slide Valve for Steam Engines ” in Scientific American Magazine Vol. 13 No. 38 (May 1858), p. 304 doi:10.1038 ...

Many modern automotive engines have some sort of variable valve ... cover with a 3D printed rocker cover which contains two small pneumatic pistons that push against the spring-loaded valve stems.