The internal combustion engine, for all its mechanical sophistication, still runs on a 19th-century mechanical idea: pistons rising and falling, a crankshaft spinning, a steam-age architecture ...

The rotary engine was an unconventional design that delivered great power for its size. Here's what's good and bad about it.

Wankel rotary engine powered thousands of aircraft. One of several problems: It spewed castor oil on its pilots.

In theory, Wankel-style rotary internal combustion engines have many advantages: they ditch the cumbersome crankcase and piston design, replacing it with a simple, single-chamber design and a thick, ...

Internal combustion engines have long been at the heart of automobiles, serving as their main driving force over the decades. Traditionally, combustion engines rely on a configuration of cylinders and ...