Through the history of internal combustion engines, there has been plenty of evolution, but few revolutions. Talk of radically different designs always leads to a single name – Wankel.

Mazda's Wankel rotary engine has always been unique in the automotive landscape as a mass-produced internal combustion engine that eschews such unsightly items as pistons, valves and camshafts.

Although there was briefly a company called Rotary Rocket, the term is much better known as a nickname for the Mazda RX-7 — one of the few cars that used a Wankel, or rotary, engine. If you ever ...