wcs20

I am always the type to think of new ideas of what if's? so I pose this what if...
(flame suit on for possible trolls)

I was reading about Toyota's d-4s fuel injectors and was wondering why no one thinks our rotary engines (current or future designs) could benefit from it our engines use direct porting don't they so why not think outside the box a bit to make this work now the design is to prevent carbon build up on piston engines and help deliver more power and better fuel... i doubt the fuel will be possible on our cars but more efficient burning fuel (reliability even though the rotary and reliability are rarely put in the same sentence) and possible power increase are possible and I know there would be certain issues as to how it would probably operate on our current systems but come on we should think outside the box and see what rotaries could become... your suggestions please and who knows maybe someone (cough, cough) could develop such an aftermarket design... your thoughts and Ideas please....

dozer

iTrader: (3)

because we are not Mazda. /thread

YaXMaN

Firstly, how about using some capitalization and punctuation if you want to taken seriously?

Regarding your question...

One quick google search returns
http://www.carnewser.com/news/106722...ngine-in-tweet

Did you really think that Mazda engineers have never considered applying GDI technology to the rotary with all the work they're doing on SkyActiv?

Aftermarket? The injectors aren't the solution. They are a small piece of technology that supports an entire engine design approach.

Maybe you should buy a turbonator. Yah.

alnielsen

iTrader: (4)

First of all, the rotary engine is by it's nature, out of the box thinking. The Mazda Sky technology slated for the rotary is suppose to include direct injection. You are never going get the current engine, in it's present state, to work with direct injection. new housings will have to be designed that have a place for the injector and put it at it's optimal location. It's been said that this tech will be employed in the next generation 16X engine. With the problems in the world economy at the moment we will have to wait until R&D money becomes available again to advance the design of the rotary engine.
The piston engine has had more than 110 yrs of development by 100's of companies over the world. The resources that go into it today are 100's of time more involved than Mazda can put into the rotary. Mazda has done an amazing job of developing it on it's own. Those that have a special place in there heart for the rotary will just have to be patient.

RIWWP

iTrader: (2)

Just because you haven't thought of it doesn't mean other people haven't either.

Want something crazy? Go look up information on Mazda's looks into laser ignition....

If you try to fit Mazda's methods into any pre-conceived box, they will buck that and step outside of it just because it's not in the box.

bse50

Besides... direct or semi-direct injection rotaries aren't just a dream and haven't been for quite some time.

olddragger

iTrader: (3)

semi direct injection engines are running now just like G said. With good results--but poor gas milage.
Direct injection has the obvious benefits in some engine designs, but what would the gain be with just DI in our engine for the DD? Cooler combustion? Do you really want that in this engine?
Would charge homogeny be increased? IDK? With such a long combustion chamber the charge will still be required to "travel".
It would also require another hole in the housing. Every hole the apex seal has to deal with increases its possiblity for problems. So that will have to be designed for.
Rather than Di-- I would rather see a 3 sparkplug system to deal with the end gases. Yea I know enviromental folks love us reciculating it and refiring it, but if we can fire it to begin with that would be even better. I would not be surprised if the end gases end up being more of a problem than is now recognized.

Appaud the idea here--lets think outside the box.
Give me the 3nd sparkplug, an electric water pump and a water/oil cooler.

xplod

So true..
If other companies besides Mazda had the rights to put rotaries on the public roads things would have been different now. Don't get me wrong it's amazing and unique that only Mazda produces rotaries (and they deserve a big applause for it as years ago they saw the imense potential the wankel engine has and adopted it) but just think how far rotaries would be by now if other companies were also producing them.

Automotive giants like BMW, Toyota and Mercedes-Benz investing huge amounts of R&D money into rotaries.. makes you wonder..

alnielsen

iTrader: (4)

In one brief moment in time, it looked like the rotary had a bright future.
In the early 70's, the US was going to start emissions standards. Many companies bought rights to the rotary engine because they emitted a cleaner exhaust than a unregulated piston engine. This despite of the drawbacks of the rotary. The oil embargoes of that time and the introduction of the catalytic converter allowed the auto companies to continue using their tried and true piston engine. The rotary in the late 70's and into the early 80's used something called a thermal reactor in the exhaust. I don't think it was until 1982 that a catalytic converter showed up on a RX7.

I'm working for the title of RX8Club rotary historian.

lastphaseofthis

NO.

Direction injection delivers fuel only a few crank degrees before the spark plugs fire.

so the only thing that travels is the oxygen(air) that is going to be burnt?
best benefit? no more pre-ignition. the fuel isn't there until it's time to burn, and it doesn't have to travel.. this would be having the fuel injectors right above the spark plugs, or maybe were the dip stick goes.

alnielsen

iTrader: (4)

I remember pictures and drawings of the 16x engine. It seems to me the injector was positioned at the top of the housing.

WingleBeast

Wrong dude, injection happens a full 180-210 crank degrees prior to ignition in a DI rotary. Which is still 60-90 degree rotor rotation.

lastphaseofthis

i wasn't talking about the UNRELEASED 16x engine. i'm talking about DI that is actually in use...

if mazda has there DI setup at 60-90 degrees pre-spark. then thats what the **** they're doing wrong.


seems like they need a new engineer.

999miki

So you think there is only one way to skin a cat?

Most of DI gasoline engines at full load are injecting during intake stroke, for charge homogenity. Injection in final stages of compression is usually used only for low load operation.

Biggest promise as far as power goes, is shown with injecting just after intake closing. According to the research paper I have, it allows highest inlet pressure (flow) and at the same time, lowest temperature and pressure after compression, which is a good thing as otherwise, these are just pumping losses and contributors to detonation.

True direct injection on wankel engines has been done more than two decades ago and as far as fuel consumtion goes, with very good results at extremely lean mixtures and turbocharging. At that time, it didn´t worked that well with more "normal" AFR and higher power (power output controled solely by fuel flow), as injector positioned at TDC wasn´t able to create desired charge homogenity and detonation was imminent in these conditions.

Even DI won´t change inherent flaws of rotary, trailing squish flow still limits burn rate.

olddragger

iTrader: (3)

well said.
OD

pdxhak

iTrader: (2)

Plenty of pics of the 16x in my album

https://www.rx8club.com/members/pdxhak-1124-albums-pdxhak-16x-181/

TeamRX8

iTrader: (25)

would someone please consolidate this stupid thread with the other duplicate stupid thread he started in what would have been the appropriate forum to have a stupid discussion about it

https://www.rx8club.com/showthread.php?t=229360

WingleBeast

Could you exlaine how an injector set at a phase 'a few degrees from ignition' could properly provide a good mixture at WOT and also an effictive lean burn injection (near a spark plug, leading edge of the rotor). Since the combustion chamber is literally moving around inside the houseing (unlike the stationary engine block in a piston engine) you would need a different injector for each. Plus I am not sure how well an injector (full of pressureized fuel) would do on the hot side of an aluminum rotor houseing. If you have ever taken apart a rotary you will see there is not much room at full compression for any sort of swirl or spread of a single injection across the entire very long but very thin compression site, the rotor face damn near touches the houseing wall.

alnielsen

iTrader: (4)

I guess my memory is still working even at my advance age. Thanks pdxhak

Agreed and Done

wcs20

Yes I posted on wat I thought may not be the right thread I was just wondering if Toyota was using a semi port injected wit a combination of direct injection ... although it seems that negative attitude is more common .... just saying

wcs

iTrader: (2)

Hope you're not trying to hijack my Alias wcs20

slvrstreak

iTrader: (3)

I just figured that was your troll account
and now you post here in an attempt to throw us off the trail

wcs

iTrader: (2)

lol you've over estimated my intelligence, that will surely be your undoing!!!! Mouhahahaha

Are you pondering what I'm pondering Pinky?

EErrrrr ummm hey wait that didn't come out right

lastphaseofthis

please..... you're not informing me of anything. and i don't have the answers you seek... if i did, it would be because i had the resources to build such an engine and work out kinks and failures, you know like REAL R and D. not talking about it on a stupid forum. i just hope someone, if not i, will do what i said should be done in the future.

2 different injectors? you mean like a primary set and a staged set? yeh, that will be hard to do... :D

olddragger

iTrader: (3)

isnt that another set of injectors I see more toward the exhaust side---green in color?