You may have heard your car has a four-stroke engine, but you're not sure what that means. Why are there four? And what is a stroke, anyway? A modern gas engine most commonly uses pistons and a ...

The story of how Honda developed an oval-piston race engine that ultimately failed but still made history along the way.

Diesel engines, for all their rugged usefulness, can be tremendously polluting. They produce more NOx — nitrogen oxides-based emissions – than gasoline-fed cars, as well as more particulates, aka soot ...