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I get the idea but I'm having a hard time working out the mechanics of it, I had an idea once that had one rotor compressing the air fuel charge once before it passed another port to the second rotor for some more compression and ignition.

Kinda thought the same thing for a piston motor but in that case a screw type cpmpressor is much more efficient than any piston type compressor.
 

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Discussion Starter #82
Wouldn't that start to break down the simplicity of the rotary design? I mean it would most likely bring in a host of new headaches for reliability and longevity.
 

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I have also thought about strictly timed sequential port injection, but my thought is that even at low RPM where the problem is most prevelant the time between the exhaust being closed off and the intake being closed off would be very small. (you could actualy start injecting some time before hand but not much) That would require primary injectors of a much larger than normal size to flow enough fuel in a fraction of the time a normal set would have.
Its been done, about 10 years ago a shop here locally did a sequential port fuel injected PP 13B to show how well the particular brand of after market ECU they were using could work. should be no problem on a j-port/bridgeport/extend port motor if it'll work on a PP
PP motors have a ridiculous amount of overlap, and normally with carbs you cant get them to idle under 2000rpm let alone produce any torque.
This sequntial port injected version idled at around 900 and was producing torque at 2000rpm and went on to make 400hp at 9000Rpm on the engine dyno.
The article was in one of my old car magazines, I probably still have it, but I dunno where, prolly in a box somewhere in the garage.
 

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Discussion Starter #84
Thats bad ass, direct injection FTW. I wonder if Mazda has thought about doing this on the new Renesis engines. They do it on the new MS3 & 6.
 

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Wouldn't that start to break down the simplicity of the rotary design? I mean it would most likely bring in a host of new headaches for reliability and longevity.
What I'm thinking doesn't really add too much more. It adds a lobe to the crank/eccentric shaft, similar to a cam in shape. It also add a moving "deep" point in the rotor as opposed to a fixed one. and Maybe 2-4 springs per rotor face(on the 'inside of the rotor, which would mean creating a 2-piece rotor). But my design eliminates the peanut shape which creates a shaking motion and places strain and wear on the current Rotary at Idle. My round design also eliminates the "knocking" of the Apex Seals to the housing, which would logically increase longevity. Anyways, I'm leaving work now, I'll draw it up when I get home.
 

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Chief, could you dig up that article or point me in the right direction to get the info? I figured someone must have had the same idea, I wonder if the RX8 uses the concept to any degree? Even retarding the injection by a few degrees would have an effect.
 

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Discussion Starter #88
Damn Joey that still looks like it has the chance for epic fail. Think if one of those pistons and the springs and shit fell out into the housing! But I see what you are saying and it makes some sense to me now. So the piston gets pushed up by the cam lobe once it has the intake charge and compresses it even more to get full compression before ignition and then drops back off. I am assuming that the cam lobe is stationary?
Not bad, Wankel Jr.!
 

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Yes the cam lobe stays in place and doesn't move. I was thinking about a way to get rid of the rumble or shake that rotaries have so that it could perform better at lower revolutions, this is what came ti mind. Getting rid of port overlap, keeping compression, and getting rid of the slight lateral movement that the rotor has moving up and down in the housing.
 

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Then you would need 2 lobes to make it a 4 stroke engine, the one lobe in the pic compresses the mixture on one side then allows for the power stroke to occour on the downward face of the lobe.

But theres no action to expel the exhaust then draw in an new charge.

Also where dose the output occour? If the housing and cam are stationary then you would need some way of connecting the rotor to the drivetrain.
 

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Like I said, it's just a quick idea, I haven't worked everything out, nor will it likely happen. I'm not an engineer! haha. But you do bring up a good point with the drive train. the 2stroke/4stroke is not as important to me right now...
 

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When I was going to Lincoln Tech I had an 85 11a manual. I loved that car. Decided to put a 100 shot on it and it ran great for a while until I parked it on some leaves after a hard flogging and started a small brush fire. Car was a total lose.
 

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Yes that would be weird, but no..thats not it ;)

Well, the runners are bellmouthed, so yeah They have velocity stacks. But thats not it exactly either.

No ram air. You may have missed the snorkel tube going to the bottom of the engine bay. Thats where the sealed airbox (its sealed on top to the hood) gets its air from.

The answer actually is........Variable length intake runners.

The setup is RPM actuated. I think the owner (Tom Ellam) got the idea looking at a newer sportbike (I want to say Gixxer 1000) and adopted the idea to his car. Tom is somewhat inventive :)

Gavin
Totally missed that! Yes, that makes total sense now. Thanks for pointing that little bit out!

Alright, so here is a rough sketch of what I'm thinking. It;s obviously not completely thought out, no one can design an engine in such little time and NO research, but this is my idea...
Sorry bud, no offence, but that's a colossal fail. Almost as bad as that dude that welded fins to his turbo and the guy that planed to plumb his exhaust into his intake...

The housings can't flex as they'd be under huge amounts of pressure. The "cam" you speak of is pretty much already there, it's the eccentric shaft, which acts like a cam and a crank all in one. Remember, the idea of making power and reliability is to reduce the number of moving parts so there is less mechanical actuation happening, lower part counts, and lighter mass. Adding more and over complicating it wont make rotary better, but rather worse!

The rotary design has 2 major flaws that are likely to never be addressed. Those would be the apex seals and the oil injection. The fact it burns oil and has to causes potential issues with future emissions and issues with consumers who aren't used to it and let them starve. The apex seals are not overly strong, so a long lasting rotary is not something you see all that often. The day Mazda finds a method for improvement in those 2 categories, we may actually start seeing a Ward's 10 best. But until then, it's nothing more then a cool piece of engineering that unfortunately, like the piston engine, will probably see its demise in the near future with some new advancement in eco-technology.
 

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Sorry bud, no offense, but that's a colossal fail. Almost as bad as that dude that welded fins to his turbo and the guy that planed to plumb his exhaust into his intake...
I take offense in THAT. They are just idiots. I'm actually trying to create something NEW.

I understand that less parts is best, but what I'm thinking is STILL less parts than a piston engine. Like I said, I'm no engineer and this is just the drawing I made to illustrate my quick Idea. I want to eliminate the engine rumble and port overlap, that's all. Actually putting time into it would make for better ideas, but I'm not paid for that, so I probably won't. I just thought I'd share my idea....


But thanks for encourage my creativity Matt :)
 

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Discussion Starter #95
"There has got to be a better way." - Gary Vermeer, founder and emeritus of Vermeer Mfg. Co.

A simple farmer, with a knack for tinkering and designing. Went from one design to a worldwide corporation in less then 50 years.
If this guy could come up with a better way to harvest corn, make bales, and cut stumps then who knows, maybe Joey could save the rotary.:shrug:

I'm not saying he is or that this is the idea to do it, but if no one ever tried anything different or thought about the possibilities, we would still be trying to figure out the wheel.

Hell, it wouldn't be the first time someone thought the rotary engine idea was crazy.
 

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Hey Joe, heres some more input :) I noticed that you kept the triangular rotor shape, since you no longer have the peanut shaped housing and reciprical motion the rotor can be entirely round! That would make more robust seals possible and even multiple seals.

at this point it's starting to become remenicant of old style rottary radial engines used in some aircraft, but where the output of those motors wat the crankcase it's self and the crank (and therods and pistond atleast radialy) was held stationary in this case the crank and housing are stationary while the while the rotor/piston assembly rotate.

The one issue I see being a problem is controling the pistons, especialy on the intake stroke. After the piston starts down the trailing side of the IN/EX cam you are depending on it to draw the fresh charge in, under most operating conditions the motor will operate completely on the standard induction principal, and with no positive retention of the piston to the cam we depend entirely on the return springs to keep the piston against the lobe and provide the "draw" for induction.

We have a situation similar to what OHV motors have, we need to provide enough spring pressure to keep the piston from "floating" without over stressing the related components. This would be RPM dependant also so too little spring limits RPM and too much limits the working life of components and would draw a significant amount of power.

I4, most rotaries last a very long time without failure. Ofcourse these people dont log on to let everybody know the have had no issues ;) It's the same principal thats at work on MX6.com and even Honda and Toyota forums. Look through any forum and you will see page after page of people asking why the car just broke!
 

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Its worthy of note that back in the early days of the wankel rotary's development there were a few other designs on the go.

I think its pretty fair to say that everything has been tried, there was lot of innovation during and post WWII.

Even in the early days back when NSU (now part of Audi) built the RO80 sedan powered by a twin rotor, their under development caused alot of warranty returns and eventually led to the demise of NSU.

Mazda sunk an unbelieveable amount of time and effort, and even then in the early days of the twin dissy motors, there were still problems with side seals leaking oil etc. Unfortunately it wasnt until the devlopment of the 3mm steel apex seal did reliability improve, the metallurgy just wasnt there prior to the mid 1970s to make them.

Some interesting reading below, I cant find links that are as good as my books on the subject tho.

http://cp_www.tripod.com/rotary/pg05.htm

MAZDA:History of Rotary | The Rotary Engine

Wankel engine - Wikipedia, the free encyclopedia

I am not usually a fan of wikipedia, but in this case it seems fairly accurate

apologies if this has been posted before...
 

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I take offense in THAT. They are just idiots. I'm actually trying to create something NEW.

I understand that less parts is best, but what I'm thinking is STILL less parts than a piston engine. Like I said, I'm no engineer and this is just the drawing I made to illustrate my quick Idea. I want to eliminate the engine rumble and port overlap, that's all. Actually putting time into it would make for better ideas, but I'm not paid for that, so I probably won't. I just thought I'd share my idea....


But thanks for encourage my creativity Matt :)
I didn't mean to kill your creativity, but think of it simply and the idea will come to you. Complicating it doesn't make it better, but rather worse. Although your idea may use less parts then a conventional engine, it still uses more then a traditional rotary, therefore less efficient. Your on the right track, just think of taking things away rather then adding them in.

Hey Joe, heres some more input :) I noticed that you kept the triangular rotor shape, since you no longer have the peanut shaped housing and reciprical motion the rotor can be entirely round! That would make more robust seals possible and even multiple seals.

at this point it's starting to become remenicant of old style rottary radial engines used in some aircraft, but where the output of those motors wat the crankcase it's self and the crank (and therods and pistond atleast radialy) was held stationary in this case the crank and housing are stationary while the while the rotor/piston assembly rotate.

The one issue I see being a problem is controling the pistons, especialy on the intake stroke. After the piston starts down the trailing side of the IN/EX cam you are depending on it to draw the fresh charge in, under most operating conditions the motor will operate completely on the standard induction principal, and with no positive retention of the piston to the cam we depend entirely on the return springs to keep the piston against the lobe and provide the "draw" for induction.

We have a situation similar to what OHV motors have, we need to provide enough spring pressure to keep the piston from "floating" without over stressing the related components. This would be RPM dependant also so too little spring limits RPM and too much limits the working life of components and would draw a significant amount of power.

I4, most rotaries last a very long time without failure. Ofcourse these people dont log on to let everybody know the have had no issues ;) It's the same principal thats at work on MX6.com and even Honda and Toyota forums. Look through any forum and you will see page after page of people asking why the car just broke!
Rotary engines are not known for longevity, although there are some, there aren't as many as there are conventional engines. Just by design, they wear out. But in defence of rotary, when they need a rebuild, the traditional piston engine needs a timing belt or some other form of heavy service. Both have their ups and downs, but my comment was made more as a general comment. In other words, you don't see 700,000-1,000,000 mile rotary's, but you do piston. Not to say it hasn't happened, but its not likely to happen as often as it does with others.

I do like the idea you present about a round rotor chamber. Seals wouldn't see the regular wear being closer in tolerance, but the downside is the eccentric shaft would have to be PERFECTLY balanced to insure long life. Not impossible. I'd love to see someone draw that up really.
 

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two things kill a modern rota, lack of lube and heat/detonation. If the owners are aware enough to keep those two things in check then theres no reason a rotor cant last nearly forever.

I dont see where you got that rotaries "wear out" by design. Apex seals being the most common and usualy only point of failure can go hundreds of thousands of miles with next to no wear.


Now the real world situations are much different, owners just dont maintain their cars well at all and the wankel dose not tolerate that very well at all.

My MX6 on the other hand showed many many signs of neglect. The oil was dark and thick and under the valvecovers was a significant amber buildup. But a few oil changes over the course of about a thousand miles had it all good. The compression is dead even across all six cylinders and the cam lobes and tappets look like flawless chrome.

But my first year with the car was a series of overheating and coolant loss frustrations. The coolant had been neglected to the point of turning deathly black and turning very acidic. I had to replace every single piece of plastic in the system including the radiator because it was nearly completely disolved.

This block will never see significant boost because the block has ben eroded away by years of bad coolant. If I ever pull the heads I expect the heads and block to be warped to the point of being garbage.

Most motors wouldnt fair this well under similar treatment so i wouldnt blame a rotary for simply losing compression after 70K miles of abuse. Also keep in mind that that < is exactly what most "broken" rotaries are. Simply engines woth lost compression and power. It's near impossible to actualy KILL a rotary.
 
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