Beating rhythmically underneath the hood is the heart of the the RX-7 and RX-8 — a Wankel rotary engine. Wankel is such a funny sounding name, but the rotary engine (originally conceived and developed by Dr. Felix Wankel) is much more energy efficient than a typical combustion engine with pistons and cylinders. In a piston engine, the same volume of space (the cylinder) alternately does four different jobs — intake, compression, combustion and exhaust. A rotary engine does these same four jobs, but each one happens in its own part of the housing. It’s kind of like having a dedicated cylinder for each of the four jobs, with the piston moving continually from one to the next.
The Wankel engine has basically one moving part that just spins. And it has a higher power to weight ratio than any traditional engine. Mazda’s RENESIS engine in the RX-8 is remarkably smooth and high revving — all the way to 9,000 rpm — and offers a smaller engine footprint than traditional internal combustion engines. In fact, the packaging and styling that define the RX-8 would not have been possible had Mazda engineers chosen a conventional piston engine.
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