Rotary engines differ from conventional ones in many respects — and one of them is the fact that they use two different spark ...

Pop the hood on a classic Mazda RX-7 or RX-8 and the engine bay looks oddly empty. That is the charm of the rotary engine: a compact lump of metal that trades pistons and valves for a spinning ...

Perfectly tuning the heat range of an engine's spark plugs is something of a dark art to all but the most well versed tuners and the engineering egg heads at automotive OEMs. Getting the spark plug ...

In a world dominated by pistons, the rotary engine was something different for motorists. It was the vision of German engineer Felix Wankel, built on the belief that the up-and-down motion of pistons ...

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, ...