R_PROWESS

iTrader: (3)

I was thinking today about the multiple displacement thing the newer domestic cars have.. you all know what it is.. shuts off the cylinders opens the valves ect for increased fuel mileage

Anyway I was thinking on it for the rotary as many of you have.. I know this.
My idea would be to simply run on 1 rotor. I know, to do this you have to worry about the other rotor, fuel, computer ect. ect... The rotor still spining creates compression, but I was thinking on how to rid of the compression and my simple or not so simple solution would be to place a large electronicly activated valve between the primary and secondary spark plugs, this would eliminate the free spining rotors ability to create compression allowing it to spin without the rezistance the dead rotor would have created without this. ofcorse the computer would have to shut the fuel off. but in effect the air would be entering the engine normaly into the rotor, not doing any work, and exiting between the spark plugs. I have no idea how large the port would have to be, im guessing the same size as the intake port.

the air exiting the valve could also be recirculated if there was a reson to. otherwise it could be ran through a pipe out of the engine bay

well theres my idea it probably has 1 milion flaws but i was bored and thought I would see how many people disagree with me, or think it's an okay idea.. well go ahead.. let me hear it

ra ra rotory

This isnt a very new idea, I know cadillac used this in the 70's or 80's.

I doubt it would work well on rx7's, It feels like my S5 n/a can barely pull its fifth gear, let alone with half the power. You would be consuming just as much fuel at a full throttle cruise on that one rotor, than you would at a steady cruise at say 1/8 - 1/4 throttle on both..

Thats my worthless 2 cents

RETed

No.


-Ted

rotarygod

iTrader: (1)

Already tried it. About a year ago I was playing around with this on my 1st gen. It's a streetported 13B with a Megasquirt ecu. I could shut off fuel to one rotor on demand. The engine will not start this way. It also vibrates very badly running only on one rotor. To hold 45 mph I nearly had it floored. Overall it just doesn't work.

R_PROWESS

iTrader: (3)

so your saying you put a port between the spark plugs to releave pressure? because thats hte topic of my idea. it sounds more like like your saying you just cut the fuel and thats all you did. the one rotor would stil be working against the other that way, ofcorse it wouldnt work

R_PROWESS

iTrader: (3)

ok basicly you guys are saying a 1 rotor car would get worse gas mileage on the highway than a 2 or 3 rotor car? if you completly eliminated compression to the rotor that is doing no work, the only rezistance that rotor would be inducing on the rotor that IS doing work, is it's own free spining weight... exactly like the v8s

rotarygod

iTrader: (1)

For some reason I completely missed where you said you wanted to relieve the pressure of compression. That's an idea. On piston engines with DOD, they close the valves completely. They still compress whatever air is in there but it should be much depending on when they closed the valves.

RETed

I guess you're totally missing the part of BALANCE.

You're combusting on one rotor and not in the other?
Don't you think those forces would make things rather imbalance?

The reason why you can get away with it in many cylinder engines, cause each cylinder only affects a small angle on the crankshaft rotation.
V-12's are a natural, since each piston only affects 360 / 6 = 60-degrees of crankshaft rotation, and then you need to figure in that each cylinder is reinforced by another cylinder in the opposite bank.

Once you start to drop the # cylinders, you run into huge angles for which each cylinder affects the crankshaft rotation.
This means you start to drop cylinders, and you get huge problems with imbalance and resonance.

Think of a two rotor as a 2-cylinder, and you get major headaches.

It's just not possible.
You'd think Mazda would've figured it out by now?


-Ted

R_PROWESS

iTrader: (3)

for all we know mazda has come up with this, but I don't believe mazda has been trying very long either, maybe for a year or 2. how many imports do have DOD? they don't wory about it too much because they are the standard that we americans are trying to live up to fuel mileage wise. but to me it does not matter if mazda's new rotary comes out with some sort of DOD because hey, I can't afford a new car and if i coudl i wouldnt buy one. what i want is our own solution.

as for ballance this is arguable but just because lets say.. the front rotor has no compression, this does not mess up its ballacne. everything is internaly ballanced and no, you can't compare it to a 2 cylinder V engine. you would have to compare it to a 4 cylinder V engine that is runing on the front 2 cylinders while the back 2 are free cycling.

RETed

AFAIK, Mercedes Benz offered it first for mass-produced automobiles.


You're ignoring combustion forces...

Freespinning, yes.
Under normal combustion to all rotor faces, yes.
Misfiring one of the rotor faces? No.


Not true.
A Mazda 13B runs a ratio of one rotation of the rotor to every 3 rotations of the eccentric shaft.
Then you need to take into account of the front rotor versus the rear rotor.
The rotors are phased 120-degrees apart but x3 for eccentric shaft position.
In reference to the rear rotor, you get each rotor face (both front and rear) phases 60-degrees apart, but adjust for eccectric shaft position that comes out to 180-degrees separation.
This is almost like an inline 4-cylinder if anything?
Remember, there is no reinforcement in this configuration like is most V-configuration engines (i.e. V8, V10, V12).
I dunno how a V4 fires?
Still 90-degree separation of piston position or it's just as reinforced 2-cylinder?
You induce a lot of nasty harmonics when you misfire the engine...


-Ted

-Ted

89FC3S

you will also have to look at how much pressure is going to be on the seals of the one rotor and if they will be able to hold and as for fule shut off you could just run a relay off you injectors and cut it wen ever you want but i think what you would have to do is come up with a new ECU that would still let you use both rotors but only alternating faces i think that might help you also with any balance problems and would take some of the stress of just one rotor if you were to have the other one dead just my thoughs