An engine is an engine, right? Well, no. Some are just more engine than others. This list includes 10 of the engines that changed the auto industry.

The Knight sleeve valve engine used the four-stroke Otto-cycle system present in most modern vehicle engines. Starting with the piston at the top of the cylinder, the crankshaft's rotation pulls ...

There are several variations of engine design that have been experimented with over the years, such as the Knight Sleeve ...

[Tom Stanton] has designed and made a couple of air-powered 3D printed engines ... the sleeve seals create a plug with an o-ring, while the pin pushes open a ball which acts as the inlet valve ...