The Wankel engine in the Mazda RX-8 houses a rapidly spinning cam that is shaped to compress and combust fuel and air against the inside of an oval chamber.

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Japanese exporters gained as the yen weakened, with Honda Motor rising 3.8%, Mazda Motor climbing 4.6%, and Sony zooming up 4.8%.

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Also affected under the same recall were the RX-8 and Mazda 6 at Mazda Motor Corp.

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