HiWire

Has Mazda finished with the development of 3-rotor engines? I know there were a few winning 20B cars in JGTC, etc., but is there more factory involvement or is it all privateer tuning at this point?

The Renesis has admirable power and emissions for its displacement, but I can't think of any other rotary setup with the same kind of torque.

2RotorsNaDream

iTrader: (7)

The Furai is a 3 rotor, and the Rolex GT Series' RX-8s have 3 rotor engines also. I'm not sure if Mazda officially has anything to do with the Rolex cars but the Furai is definitely all them.

rx7rcer09

Mazda is a very race oriented company. i would think they will keep pumping out race cars sporting a Rotary engine as long as it falls in race rules. the rotary is Mazda's baby so i dont see them letting it die any time soon.

Turbo8

iTrader: (17)

Actually, the Furai's ethanol powered 3-rotor engine was designed, assembled, and installed by Racing Beat:

http://www.racingbeat.com/mazda/perf...zda-furai.html

Really cool project, but Mazda was still very hands-on during the entire process.

t-von

iTrader: (8)

My hope is that Mazda eventually starts developing more displacement versions of the rotary. The new 16x is getting close and it will have more torque than the Renesis. I think the torque will be a substantial increase because of it's longer stroke and not just because of it's larger displacement. If they are successful with the 16x, I see no reason why they can't do a 3 rotor version for a higher end vehicle. Toyota & Nissan have their high end premium sports cars. It really bugs me that all we have is the Rx8. Now that Ford is no longer in control, ya neva know.

Fortune_Seven

iTrader: (24)

I love the Furai so much!!!

arghx

iTrader: (3)

Peripheral exhaust ported rotaries like the 20B and 13B-REW of 20 years ago are dead. They are too dirty. Even the Renesis, which is far cleaner than the REW ever was while still using less emissions equipment, is now too dirty. That's why Mazda can't sell it in Europe anymore.

Mazda can't even get their 2 rotor 16X Sky engine prototype to meet their goals yet and it's been in development for at least 5+ years. And I'm not convinced the final production engine will be 1.6 liters either. The entire industry is downsizing engines. It's only a matter of time before they do it to the rotary. Mazda may take the basic geometry of the 16X (thinner side housings, two plugs spread further apart) and put it in an engine with lower displacement + some kind of electric or turbo assist.

I have seen the most recent published patents, which are admittedly a couple years old now. There are two possible geometries in development. There are a couple different configuration of direct injection being tested, with the latest being 3 injectors per cylinder (two direct injectors + an injector in the intake port). All the diagrams indicate a 6 port, naturally aspirated engine that is basically a refinement of the current Renesis. There is some exotic stuff (for auto applications) that Mazda is working on, like a plasma spark plug that have never been used in a production vehicle before. The plasma ignition has already been patented. Remember that Mazda is ahead of its time. It had a Miller cycle engine in the Millenia before Toyota adapted the process to the Prius engine.

Consider the 3 rotor dead except in some lab somewhere maybe. There is no future for it except in a super car that Mazda has no chance of devoting money to. You realize that if fuel economy regulations continue, basically every passengar car gas engine will be a small displacement turbo + turbo or electric within 5 to 10 years? BMW is already readying their 3 cylinder for mass production on front-wheel-drive applications. The downsizing trend is all over the mainstream media and all over the journals and research publications.

GodSquadMandrake

^What you said is true, but kind of sad. Times have changed a lot. It used to be something special to have a turbo, but soon every car is going to have one. As soon as I catch up on tuning it's all changed.

neit_jnf

iTrader: (17)

Mazda has stated that the downsizing + turbocharging trend is not something they are too interested in. They want to go HCCI - Homogeneous charge compression ignition, the first step towards this is the 14:1 compression sky engines.

arghx

iTrader: (3)

It's true that Mazda has taken an alternate direction, partly because Ford doesn't have a controlling interest in them anymore. I think that's pretty cool. A few manufacturers might follow the super high compression ratio, naturally aspirated approach for one or two engines here and there. Overall though most manufacturers are going with downsizing + turbo or electric to varying to degrees. BMW is one of the most aggressive adopters at this point.

None of that will make the 3 rotor come back as a production engine however...

rx7rcer09

as stated the rotary is a very dirty engine when it comes to emissions, while i would love to see new cars produced with a rotary it's becoming harder to pass smog in certain states. while i see the rotary always having a place on the track it days as a "street engine" may become numbered with stricter emission rules. I hope Mazda does all that it can to fix this problem but with them as the only company still working on a producing the engine it may become a feat too big for them to complete.

the_glass_man

iTrader: (2)

20B replacement parts have already been discontinued for years. As far as Mazda is concerned the 20B is dead and buried. As arghx has mentioned the peripheral exhaust rotary engine that we know and love is also dead.

I don't think the Renesis will ever have the same power potential as the old engines. As much as I hate to say it, unless Mazda wows us in the next couple of years we could very well see the end of rotary engine production.

neit_jnf

iTrader: (17)

They have the technology to keep the Rotary alive. They developed catalytic converters for lean combustion and have experimented with ultra lean stratified charge direct injected turbocharged rotaries for years. They just need to put it all together.

It's just a matter of costs vs benefits. Being the only ones working and actively experimenting with the Rotary is a costly endeavour.

the_glass_man

iTrader: (2)

I wish Mazda and Lotus would partner together to make an all Aluminum (Rotors, Housings) engine that they could share between platforms and share some of the development cost. Lotus could really benefit from something other than the run of the mill Toyota engines they've been using over the last few years.

arghx

iTrader: (3)

They already have all aluminum housings now on the prototypes. They probably deemed that aluminum rotors were too expensive.

GodSquadMandrake

He's the director of North America R&D only. Although being a director, I'm sure he knows what's happening here at the Yokohama R&D center too where they've developed the rotary engine since 1987.

http://www.mazda.com/mazdaspirit/rot...t/event02.html

Cgotto6

iTrader: (8)

Although I know your right, I seriously drool about the possibility of aluminum housings, plates, and rotors. Would be the gnarliest package ever!!

GodSquadMandrake

Well I guess he would know better than I do. I just want to keep wishing for a new RX7 to come out.

arghx

iTrader: (3)

^^ I know this amounts to nothing more than internet hearsay, but did Mr. Hiraishi tell you anything that you wouldn't be able to find in a press release? Basically all we've heard since the 2007 prototype display is "yes, we're still working on a new rotary, but it's taking longer than we thought it would"

and there have been rumors swirling around about the prototypes: cooling problems, missed emissions targets, problems getting it to rev out reliably, concerns over weight, multi-fuel capability (which Mazda has had in labs for decades), various forms of assist (turbo, electric)

Taylorjones

im pretty sure ford supported the piston engines that they threw into there cars lol... but they can still work on a rotary if they like over in Japan :p ... Ford has nothing on that lol

Barry Bordes

The way that direct injection transformed the 2 stroke engine as in the Evinrude E-TEC series may certainly help with our rotaries.

Hydrogen seems well suited for our movable combustion chambers also.

I won't even mention using active radical combustion utilizing overlap gasses...... or not.

Let's hope,
Barry

greenday_5606

I think if they ever actually bring the 16x into production that it will do great. I mean going aluminum instead of cast iron is already a plus. Naturally aspirated is also if it actually has a good amount of power to it. The one thing I did not quite understand about their development is thinning the coolant passages. That does not sound like a good idea to me but who knows mazda knows best for these cars; well accept for some of the flaws they have produced in them such as accelerated warm up and other nonsense. I feel like they are definitely putting their time into it though because they have been working on it for over the past five years. The main thing that is really holding back the potential of the rotary is emissions. Hydrogen I do not know how well that will ever go. I know they have testing their engines in the rx8 but I havent really looked up all the specs on those. I hope they put out the new 16x soon though or at least give us some more information on their developments. I also heard rumors about the rotary mazda 3 which would actually be pretty cool. As fair as retaining the gas milage that the 3 gets; well that seems a little far fetched with a rotary.

Just my two cents

Shannon

arghx

iTrader: (3)

I'm not sure where you get that from. I don't recall seeing anything specific about thinner passageways in the 16X prototype they displayed a few years ago. There is some grumbling because the current Renesis cannot really be ported on the intake side due to the thickness of the casting in the irons. The Renesis already has significantly bigger intake and exhaust ports compared to the s5 Rx-7 non turbo engine in stock form. The 16X will have completely new castings for all the housings. The Renesis was basically modified s5 non turbo irons + REW rotor housings with the exhaust ports undrilled and coolant o-ring grooves installed, like the pre-86 13B engines.

they don't have the accelerated warmup system on the Renesis. All they have is an electric airpump to warm up the cat. It's nowhere near as involved as the REW's secondary air system.

Yes. My understanding is that they are designing the prototype with future regulations in mind, so that they will be able to meet tightening standards and not have to redesign it again after two years.

Some of the technology in the Hydrogen Renesis, such as direct injection and dual fuel, is being implemented or at least tested in some form on the new prototype.

The only front wheel drive rotary Mazda had was the 13A, which only lasted a year or two.

It might get the mileage of the outgoing 4 cylinder but not the new Sky gas engines which are hitting 40+ mpg without a turbo or electric motor.

neit_jnf

iTrader: (17)

this is clearly visible in the pictures and diagrams, they kept the outside size of the engine the same while increasing the size of the epitrochoid and the rotor resulting in thinner coolant passages

j9fd3s

iTrader: (3)

it was dead in 89. the story i heard was they put an extra cat into a 3 rotor cosmo, and it promptly caught fire. if you guys think the FD was too hot, the three rotor is 50% more.... there are some circa 1989 rx8 badges floating around....


it does, no backfires! they have been available in japan for a few years


i think they had a hydrogen rotary mazda 5? japan only again though