On The Death Of The Rotary Engine

A dream died last month.  The Mazda RX-8, the sole bastion of the Wankel Rotary engine (and the only rotary-powered car in the last decade), went out of production.  The business reasons for this aren't hard to understand.  Mazda's Renesis Rotary, an evolution of the old 13b twin-rotor dating back to the 80's, didn't meet European emissions any more.  And while it did meet US emissions, no one was buying them.  Mazda sold 1,134 of their bizarre rotary-powered 4 door sports car in the US in 2010.  Not to put too depressing a point on it, but for every RX-8 that Mazda sold in the US last year, Toyota sold 289 Camrys.  So while the concept of a four-door rotary-powered rear wheel drive sports sedan is cool, it's not one with any sales volume.

The RX-8 was not an ideal car.  Some people found some pretty stupid things to complain about when it came to the RX-8: oil consumption, for one.  If you buy a rotary-powered vehicle and you're unaware that they use oil injection to lubricate the apex seals, you shouldn't have a rotary powered vehicle.  They consume oil by design.  Poor A/C performance was another, which was easily remedied by shielding the A/C lines in the engine bay.  But the big problem with the RX-8 from a normal person's standpoint was fuel economy: terrible.  Always has been, always will be.  Rotaries are thirsty.  From an enthusiast standpoint, the problem was more specific: we don't really care if our car gets bad gas mileage.  I doubt any Ford GT owners complain about getting 12mpg.  The issue was that the RX-8 was a very thirsty car, but not a particularly fast one.  I suppose it would be the MPG to performance ratio.  From a personal standpoint, I never liked the way the RX-8 sounded: one of the few cars that almost universally sounds worse with an aftermarket exhaust system.

Still, for all the gripes (really, 15mpg and 150lb-ft of torque?) there was a lot to love about the RX-8.  Primarily, the chassis: the relatively long wheelbase, low mass, ideal weight distribution and low moment of polar inertia made the RX-8 (at least those equipped with good suspension, wheels and tires) a supernaturally nimble car.  Few cars I've driven have had steering that impresses like the RX-8.  Motor Trend agreed, placing the RX-8 high in a recent handling test against some much more modern, and much more powerful cars.  It's no Lotus Elise, but there isn't another car with airbags and seats for four actual humans that delivers the kind of nimble, approachable attitude the RX-8 delivers in spades.

Other things delight as well:  What the rotary lacks in overall grunt, it makes up for in character.  The powerband is unique: the Renesis happily spins to 9,000rpm without sounding or feeling particularly stressed, something that only a handful of other roads cars can manage.  One is the first-generation Honda S2000, and the rest all have six-figure price tags.  The shifter on the six-speed RX-8 is perfect, the interior is still pretty cool and the seats are great, etc.

News outlets have been saying for years that Mazda is working on a replacement for the Renesis, called the 16X.  It apparently would be emissions-legal everywhere for a long period of time, have larger chambers (which means more displacement), significantly better fuel economy, considerably more power, and lots of tech.  And perhaps they really have been, but I wouldn't bet the bank on ever actually seeing the 16X under the hood of a car you can actually plunk down cash and buy.

The automotive manufacturing realm has no room for outliers like the Rotary engine.  It has no room for outliers of any sort.  Look at some of the different technologies that have come and gone in the past, and you wonder how the Rotary stuck around as long as it did.  Mazda's supercharged Miller-cycle V6 (in the Millenia S, remember that?) - great idea, but no one else hopped on that band wagon.  Mitsubishi's "twin stick" four speed in the Colts of the 80's - basically a 4-speed manual with a 2-speed electronic transfer case allowed for more gears and less cost than an actual 8-speed gearbox.  But you don't see a whole lot of passenger cars with transfer cases.  Sure, some off-road oriented SUV's still offer one (but it's getting rarer.)  And the concept there is different; they offer a normal gear for road driving, and a super-low ratio for off-road use.  Road-biased transfer cases like the Colt (as well as the 4+3 Doug Nash transmission in L98 Corvettes in the 80's) had a regular ratio, and a taller ratio for increased fuel economy.  Some cars used to have an auxiliary overdrive gear that was activated electronically - Volvo 5-speeds come to mind.  GM was kicking around a prototype engine that could run on both the Otto cycle (low-compression spark ignition) and the Diesel cycle (high compression heat ignition) for a while called the HCCI, but where is that?  Saab had a variable compression-ratio head for their B-series 4-cylinder that was functional, but went nowhere.  Volkswagen sold a twin-charged (turbo and supercharged) 1.4L engine in the Euro market that made power like a 1.8 or 2.0L engine, but now it's gone too.

There are good reasons why all these technologies died, and there's a good reason why the Rotary is probably dying as well.  The supercharged Miller-cycle V6 wasn't particularly fuel efficient and was far too complicated to be worth it.  Transfer cases are another potential failure point that people would rather not deal with; ditto electronic overdrives.  Those HCCI engines will probably fall by the wayside due to over complexity, which is what did in the twin-charged VW motor.  BMW is working on a triple-turbocharged diesel engine; how long do you think that will last?

I've gone on at length about the rotary engine before; I wasn't particularly nice about it.  I'm not a huge rotary fan; they make no torque, get awful gas mileage, suck down oil, blah blah blah...

httpvh://www.youtube.com/watch?v=Jebl2pWaiWI

But ohmygod that sound is incredible.  Nothing else in the world has the aural intensity of a free-flowing, peripheral ported rotary engine.  brapbrapbrap brrrZIIIIIIIIIIIINNGGGGG brapbrapbrap.  It's unmistakable.  And let's not forget the Rotary's ability to spit fire.  Due to the fact that they all run super-slobbery-rich, especially tuned, you get fun stuff like this.

httpvh://www.youtube.com/watch?v=0GsNdHej1qM

Rotary engines never made a lot of sense for daily-driven street cars.  I'm sure if the development money that's been thrown at piston engines over the years (or even a small percentage of it) had been invested into the Wankel, we could've had lots of tiny little Dorito spinners under hoods everywhere.  But that's what this industry does: by nature, it squashes radical innovation.  Not having pistons is pretty damn radical.  And that's probably what will happen with the 16X rotary engine: Mazda, as a company, wants to make money.  They have to do that to survive.  So they'll probably divert that funding to developing more fuel-efficient gasoline engines, hybrid drivetrains, little pretend-SUV's, and other things with higher profit margins and return on investment.

That's how business works.  And it sucks.  So I shed a single tear for the death of the RX-8, and the Rotary itself.  There'll never be another quite like it.