olddragger

iTrader: (3)

totally agree. Actually the rotary prefers to not accelerate and decelerate. it loves running at a constant state high rpm. Thats one reason airplane guys like it.

Peekabooo

iTrader: (1)

wow sounds amazing

oltmann

Lasers, yes, but also quasicrystal coatings for the housings.

UrbanOcho

iTrader: (2)

This was the talk of our rotary meet last Saturday. Everybody is so stoked.

rotarygod

I've been hearing people say the rotary is dead for the past 20 years. I've also seen those people proven wrong every time. I doubt the rotary is going anywhere any time soon. It may not be offered in a street car continuously without a gap but the concept will never go away and someone will always be trying to improve it.

HiFlite999

iTrader: (2)

No engine likes to run at varying speeds. With constant speed, all kinds of engineering problems disappear. Piston car engines of late with EFI and VTEC do a pretty good job, but all are inefficient at low rpm and few would run at full throttle all day long out-of-the-box. Quite true, that the lack of valves in a rotary makes it much more difficult to achieve comparable flexibility. Again, as far as airplane applications are concerned, I'd never ever choose a rotary over a good ol' ancient tech Lycoming O-360 for a trans-Atlantic flight, or even out over Lake Michigan. As far as I'm aware, not one Wankel rotary has ever been FAA certified or used in an FAA certified production airplane. The word "Experimental" pasted to the sides of rotary-powered planes is there for a reason.

9krpmrx8

iTrader: (46)

I would never get in a plane powered by a rotary But I love them

User24

iTrader: (1)

I'm not worried about the rotary being dead. I know they will make a new one sooner or later.

I'm worried that it will be an upscale sedan (Shinari) with 280hp. Something that none of us want.

Or the Miata merge. Such a cutesy platform is unbecoming of the rotary.

You're going to loose money anyway Mazda, just make a hardcore, low to the ground coupe.

R80MAV

Huey52

iTrader: (2)

Or sea bass.

btw: Audi is still pursuing a single-rotor generator for a potential EREV as well. German design but supposedly consulting Mazda.

tjbourgoyne

Lazers are very costly, they are just starting to get the technology in TVs and those are around 7K. The TV lazer projection prototype was developed in the late 70's and they still can't get the cost down enough though the benefits are impressive...better picture, it never fades, and requires much less the power than of flat screens today.

If Mazda is serious about doing it I think it's going to take longer than a couple of years. I'm not being a negative nancy just realistic. I think the reality is 5-10 years down the road. Then you have to factor in every other car maker will develop the technology so now you are right back to where you started.

RIWWP

iTrader: (2)

You know that there are varying grades of lasers right? You can't use TV laser tech as a basis for combustion engine ignition tech. One is a high heat focused discharge without a concern for people's eyes or a precise color, the other is incredibly fine tuned color based that must provide the pinpoint accuracy and precise color without damaging the screen or peoples eyes. The location accuracy of a TV is far beyond that of what an ignition laser needs to be.

I'm not saying that your estimate on time is wrong, but your reasoning for that estimate is.

olddragger

iTrader: (3)

Good info hyflite. I didnt know the FAA had never certified the rotary engine.
The apex seals are more happy during constant state rpm/load. Heck the rotary even tolerates a lean burn condition ok at light load.

Forget the laser ignition guys--its not going to happen, Great in therory, mega problems when it comes to delivery and reliability. Ion stream ignition will be the thing--no grounding strap etc and it will reach inside the combustion chamber. That is one of the big drawbacks of the rortary in it's current form--where the spark has to oridginate. Look at the trailing plug. I dont even see how the trailing plug can fire any combustion at all--so to speak. It is so damn isolated and how does the flame propergate from that semi enclosed spot? Geez.
Sometimes I wish we had a 3 sparkplug design---hehehe.

RIWWP

iTrader: (2)

OD, knowing you, you might get a kick out of my posts in the parallel thread for this article: https://www.rx8club.com/general-automotive-49/skyactive-r-rotary-229982/

Too wild? Maybe but maybe not

Agreed, probably a non 'laser', even if it's described as such by the masses.

HiFlite999

iTrader: (2)

Given the articles comments about sealing under varying conditions, consider a rotary airplane engine at full throttle, with a "constant speed" propeller (fixed rpm). At sea level, you get max chamber pressure (and max hp). As one climbs though, the outside air pressure falls off, together with the BMEP and HP. Somewhere in there would one cross a range where apex seal blowby becomes a problem? Dunno. In a car, you'd likely only cross that condition for brief intervals - an airplane might run there long enough to cause seal heating and failure.

Off topic kinda, but might imply that a carefully matched and programmed turbo might be used to adjust chambers pressures in such a way that these sealing 'resonances' are avoided.

bse50

Well, it looks like Mazda took the easy way and improved sealing with "mechanical" changes and trochoid shape... A turbo wouldn't really solve the issue in my opinion as pressure is only part of the equation. Chatter marks are usually created by low rotor speeds and weak springs that let the apexes rattle.
A turbo wouldn't be a bad thing though...

RIWWP

iTrader: (2)

From the othere thread:

bse50

Quit stealing my ideas... 'nuff said!

TeamRX8

iTrader: (25)

may also equals may not

tjbourgoyne

I'm aware the specs would be different for a TV opposed to a car. My point was more on the lines of cost/benefits. It's barely feasable right now in a TV. I could justify spending 7K on a TV right now considering the picture will never fade and it burns much less power. If it last 10 years I would have bought a couple of TV's with the current technology, then factor in the money I saved on electricity. I would probably do a little better than break even.


Thing is, Mazda doesn't even have a prototype yet, or one that I'm aware of. Even if they did, it would take years to hit the middle of the cost/benefit curve. The estimate in the quote of a couple of years...it seems way off.

RIWWP

iTrader: (2)

I agree that "laser ignition" is still farther off, and not too near.

But saying that it's far off because TV tech still costs $7,000 currently is like saying "hydrogen powered flashlights are crazy expensive, so we won't see handheld consumer flashlights for a long time to come." It's different technology, different companies developing it, different goals, different markets, etc... One can simply not relate to the other.



Yes Team, "may" is an often overlooked word. I take the entire tone of the article to be "we think we found something, and have to test it to see if we are right. We could be wrong."

missinmahseven

Obviously you've never seen a 1st-gen Rx-7. When it came out, a lot of people said it was cute, in a derisive manner. Well, 30 years later it's highly coveted and finding an un-molested, un-modded example is a hard thing to do.

As for an upscale sedan, uh, I think my Shinka qualifies except for the quality of the interior build. And I guess you've never seen the other Cosmo, the big luxo-barge with the 20B in it. Yeah, Mazda's made a fat whale of a Rotary before. I wouldn't mind one in my collection.

I say build another 1st-gen Rx-7. Light, simple. Don't even give me power windows or power seats (I'm serious here.) Just four wheels, a brilliant chassis, a brilliant engine, and brakes that'll pop the eyes out of their sockets. Still make it nice, tho -- nice leather everywhere, metal instead of plastic trim rings on the instruments, nice switches, etc. Keep it under 3000 pounds.

But perhaps more importantly, after the FD and now the FE's rather iffy reliability reputation -- offer a 250,000 mile no-questions-asked warranty on the entire car, from head to stern, top to bottom.

Heh.. I just realized, the next Rotary chassis code may well be FF.. A F?@#ing Fast Rotary Rocket. All motor, baby. I don't want teh turbos. Put 300 hp NA wankel at 9,000 revs in a 2500 pound car, and you'll have a monster.

Oh, and what's wrong with "upscale?" It's the direction Mazda's going in -- deal with it. To me upscale doesn't have to mean expensive or heavy. It just means nice. I consider a Mini Cooper S upscale. It's well made, well trimmed, and it just doesn't have that sh*tbox feeling the original did. Even the new Fiat 500 doesn't have the sh*tbox feeling the real thing had.

If upscale means leather seats, satin stainless rings around the instruments, leather panels and pulls on the doors, and a superb hi-fi, I'm all for that, yup. As much as I loved the FB and the NA, they *were* built out of sh*tbox parts. And then there's the bizarre fact that the inside door handles for the NA miata came out of the Aston parts bin. Not for price -- for weight.. or rather, lack of it.

All of this is academic, tho. Mazda, make the engine stupid proof, granny proof, drive-it-once-to-get-groceries-and-never-get-it-hot proof. Back it up with a seriously ballsy warranty. Otherwise, after the FD and FE reliability issues, no one will trust you again.

I still will. This is my favorite engine, with the Ferrari twelves a close second. The rest are just back there, somewhere.

dynamho

I've read about ignition on the the rotor and also lasers, but has this been mentioned?

What if the spark plug pops in and out mechanically like a valve in an interrupt-style recip engine? What if instead of linearly bouncing in and out, the motion is a sweep inside the combustion chamber, like an elliptical machine?

Would hysteresis kill the plug?

I guess a new sealing problem is introduced with a moving plug, as well as other problems typically related to valvetrains.
Oh well, speculation is fun.

dynamho

Looks like a movable core spark plug was filed in 1939.

PDF link: http://tinyurl.com/74pqzxz

pistonhater

I cannot conceive how is it that they changed the shape of the housing.

I've read documents explaining - mathematically - how the shape of the housing as we know it is the one and ONLY shape that could make the rotary engine work. Felix Wankel has been praised in the engineering world for decades for coming up with that shape/design.

Perhaps I misunderstood the article.