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Disappointing to see it as just a range extender, but I guess Mazda has bigger fish to fry with the Skyactiv-X.
Having the rotary as the range extender would allow the engine to run at a single speed for the sake of efficiency. Not as much fun as the rotary being the sole means of propulsion.....but the electrification march is relentless.
 

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Wankel engines are a mechanical wonder, but they have filthy exhaust emissions - even the very best need to have oil injected into the combustion chamber to lubricate the rotor edges (there are no "non-combustion" chambers in a rotary engine), so in that respect they're more like 2-stroke engines.

Perhaps by keeping the operating temperature lower (and they do say there'd be no turbo), they can get the exhaust emissions under control, because otherwise, a Wankel makes for a great generator: compact, lightweight with high output for its displacement...
 

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Discussion Starter · #5 ·
Wankel engines are a mechanical wonder, but they have filthy exhaust emissions - even the very best need to have oil injected into the combustion chamber to lubricate the rotor edges (there are no "non-combustion" chambers in a rotary engine), so in that respect they're more like 2-stroke engines.

Perhaps by keeping the operating temperature lower (and they do say there'd be no turbo), they can get the exhaust emissions under control, because otherwise, a Wankel makes for a great generator: compact, lightweight with high output for its displacement...
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The Wankel Rotary has those traits.

After a good deal of study, improvements have come about . They address and mollify those negatives. Yet, Mazda, being the sole commercial Wankel mainstay, isn't likely to retool to incorporate them and pay a third party for the rights.

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Years ago, when I had a 2006 Chrysler 300-C SRT-8, I remember reading an article on Motor Trend of a drive to Palm Springs in a Mazda RX-8.

They loved the free-revving engine. Their key complaints were: cramped interior, useless rear seat, 200 HP and averaged only 19 MPG.

My SRT carried four people in comfort, put out 425 HP and also returned 19 MPG.

I remember thinking: who would want to bother with a Wanker engine...?
 

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Wankel engines are a mechanical wonder, but they have filthy exhaust emissions - even the very best need to have oil injected into the combustion chamber to lubricate the rotor edges (there are no "non-combustion" chambers in a rotary engine), so in that respect they're more like 2-stroke engines.

Perhaps by keeping the operating temperature lower (and they do say there'd be no turbo), they can get the exhaust emissions under control, because otherwise, a Wankel makes for a great generator: compact, lightweight with high output for its displacement...
Do people actually pay for the exclusivity of owning a Wankel rotary engine? That seems the only reason for owning one in my opinion...

Perhaps being matted to a hybrid setup will make it more practical in more consumers eyes?
 

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they were good in the RX sports cars, where the low weight and low centre of gravity and low oscillation made them ideal. High crankshaft RPM suited a sports car too...

How I discovered them was when British motorbike maker Norton used one in their bikes, and wiped the floor with it's competition class (because by dispacement, it was only about 350cc, but because three chambers each use that same displacement, it had the output of a 900)

the dirty exhaust is what kills them, though.. otherwise they do have lots of desirable qualities.
 

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Discussion Starter · #10 ·
Do people actually pay for the exclusivity of owning a Wankel rotary engine? That seems the only reason for owning one in my opinion...

Perhaps being matted to a hybrid setup will make it more practical in more consumers eyes?
.

The beauty ( if that word applies ) of the Rotary engine is that you build an Eccentric shaft for the number of rotors you need, and adjust the computer controlling the spark events ... but you add one more housing per Rotor (and spark plugs per rotor) and an exhaust manifold for the final shebang - et voíla : New engine with new horsepower. And they can get some good power. It makes for a fairly low parts count engine.

The main commercial engine is a Two-Rotor power plant. The 787B Mazda that won the 24 Hours of Le Mans ( 1991? ) - news from the way-back machine - was a 4-Rotor version which displaced the tier limit ( 3L or 3.5L - sorry ... I've forgotten exactly what ) clocked 900 HP, but which was Governor'd to ~700 HP for Le Mans ( Wikipedia ). The Wankel Rotory was banned by the controlling body thereafter.

Aficionado's build 6 - 12 Rotor screamers . To say it's a sub-culture is an understatement. It would be better if a Rotary engine builder would explain - I find them interesting.

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Well back when 4 cyl cars were noisy, rough and slow the rotary was like a revelation. This was before the twin cam revolution (started with the Toyota 4AGE 1600 with the 4v head designed by Yamaha). I did a term paper on their development when I was a senior in HS in the spring of 1973. My brother bought an '81 RX7 some years later and I recall teaching him how to drive it; they had weak low end torque but easily revved to 7,000. Then in '89 I bought a Toyota Corolla GTS with the twin cam 1600. Revved to 7,000 just as easily and cruising rpm at 70 mph was 4100 rpm. Just like a rotary, and there you have it!
 

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Toyota? Sorry, there's no way they're getting credit for introducing DOHC engines. Alfa Romeo had been making DOHC engines for cars since the 1920s, and it has produced a family of four-cylinder DOHCs from 1954 to this day, including lots of mainstream-priced performance cars from the late 1960s onward.

Independently (at that time) at FIAT, Aurelio Lampredi's first DOHC belt-driven engine debuted in 1966 in the FIAT 124, and went on to be used widely in everything from the WRC-winning Lancia Delta Integrale to the everyday FIAT Tipo (Mk1).

By the time Toyota started making its AG series in the early 1980s, the technology was well known in Europe with hundreds of thousands of owners. Yamaha and Toyota would certainly have had several Jaguar, FIAT/Lancia and Alfa Romeo (FIAT and Alfa Romeo were separate, independent companies before 1985) engines to choose from and disassemble on their workbenches...

And yes, the Toyota TwinCams, like the Honda VTEC engines, were notorious for needing to be revved to the limit before they'd move. Over here, they were a favourite of the kind of boys who drew donuts on supermaket car-parks on Saturday nights...
 

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I was about to say that about the Italian Twin Cams @KrisW. I guess that the US market did not buy many of them like the way they bought millions of Toyotas with Twin Cam engines.

While the Alfa Nord is the lighter and more exotic unit I think the Fiat one is perhaps the better all rounder with its lower cost maintenance.

As far as character goes the 4AG is no where near the two Italian units (I owned a MR2 Mk1 SC) let alone motor sport kudos....
 

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Ahh yes but the Toyota would run like a new car with next to no maintenance or breakdowns for 100k miles....
 
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