Mazda is well advanced with a new-generation rotary engine which it intends to use in an all-new sports model.

Japanese insiders say it is most likely to power a two-door coupe built in the image of the most recent RX-7, the highly regarded version championed by the legendary 'Koby' Kobayakawa, which went out of production in 2002.

The new car, likely to be called RX-9, will therefore not repeat the outgoing RX-8’s convenient but complicated four-door coupé layout.

See Autocar's rendering of the Mazda RX-9

The RX-9 will share the major chassis components of the next-generation MX-5 roadster, and should have a kerb weight around 1250kg, light for a car with more than 300bhp on tap.

The engine, known as 16X and believed to use an electric supercharger, is described as “quite a bit bigger” than the current 2.6-litre twin-rotor unit used in the 228bhp RX-8.

However, it will be considerably more efficient than the RX-8 engine, which was discontinued earlier this year because its high fuel consumption and propensity to use oil prevented it from meeting the latest Euro V clean air standards.

Read Autocar's scoop on the next Mazda MX-5

Even so, the RX-8 has been a considerable success: Mazda UK began selling it in 2003, moving up to 10,000 units annually in the early years. The British RX-8 population is around 50,000 cars. Mazda is still deciding whether the 16X engine will be configured to run on pump petrol and sold in volume like the RX-8, or become a more symbolic clean-air project running purely on hydrogen.

Either way, Mazda is determined to continue its association with an engine type it considers to be iconic – and which it used to win Le Mans outright in 1991.

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