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Wankel’s End?

July 8, 2011 by Matt

Wankel Engine

I really hope I’m reading this wrong.

In their August issue, Car and Driver reports (emphasis mine):

Only 1134 Mazda RX-8s were purchased here in 2010. The lack of interest means that Mazda will probably shelve its rotary engine later this year. But weep not, rotorheads, because salvation is at hand. […]

The Audi A1 E-Tron, a concept car revealed at last year’s Geneva auto salon, is a showcase of rotary possibilities. Like practically every future-think demonstration vehicle, the E-Tron is electrically propelled, in this case by a 101-hp AC motor driving the front wheels. To forestall range anxiety when the 12-kWh lithium-ion battery pack peters out after 30 or so miles of city driving, there’s an onboard alternator located between the rear wheels. Enter the rotary: A 254-cc, single-rotor Wankel engine provides the power to generate up to 15kW of electrical energy, stretching total range to 155 miles on one battery charge and one 3.2-gallon tank of gasoline.

Except…it’s not really the same. Nothing against the Audi per se, but as any rotary enthusiast will tell you, relegating the engine to secondary duty providing power for an electric motor may make some sense from an efficiency standpoint, but it’s a gross waste of the engine’s potential, character, and just seems, well, undignified. Better to go out in a blaze of glory like the manner in which the FD RX-7 departed our shores in ’95 rather than carry on in some kind of nursing-home existence as the “backup” to the method of propulsion du jour.

I don’t know. A first-generation RX-7 was my first project car, so I’ve been a rotorhead from way back, and I’ve been simultaneously saddened by the fact that the engine never caught on, and heartened by Mazda’s dogged devotion to it. The wording of the Car and Driver article is a bit ambiguous, and leads me to believe that they have some kind of inside tip that Mazda has decided to cancel their long-awaited overhaul of the rotary concept, the 16X (shown below).

Mazda 16X Engine

There are a number of reasons (of varying degrees of validity) the rotary never really caught on. Many of them are misconceptions borne out of ignorance, or the negative reputation, somewhat unfair at this point, the engine developed in its infancy, when the kinks were still being worked out. A few of them are more difficult to dispel, though, among them criticisms of the engine’s poor fuel economy and lack of low-end torque. Mazda’s 16X was specifically designed to address both of those issues with the first-ever clean sheet redesign of their Wankel engine. The larger rotor diameter effectively increases the engine’s “stroke,” greatly improving torque, and changes to the port design and engine management, coupled with the aforementioned rotor optimization, cut fuel consumption considerably.

I just hope I’m misinterpreting the Car and Driver article’s wording, and that Mazda is in fact continuing to inch the engine closer to production. I know it’s not as fashionable as, say, a hybrid or pure electric system, but the engine is Mazda’s heart and soul, their primary claim to uniqueness, and is one of the few really different pieces of core automotive technology out there.

Filed under: Mazda, Rotary, Technical

1 Comment

  1. Jason Nalley says:

    Sadly, the 16x will not see the light of day any time soon. Mazda’s CEO has confirmed that they will completely devote their resources to SKYACTIV engines from this point forward. I really wish it wasn’t the case, because the 16x looked very promising.

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