Yeah, sound like the O2 idea is a good one. Idle the three without an O2. Im not sure how the ecm would react if the injector was inactive...im guessing even if it did recognize it, it would still carry on as expected, not sure....hmmm.



Im not disagreeing, just kinda suprises me that the rings would leak that much, and at that fast a rate, considering you expect them to be able to hold a fairly tight seal for combustion/compression stroke and prevent blowby. Ill just live with it works and be happy...

Cause when I think in terms of testing cylinder compression psi, on non running engine, 130+ psi pressure is held for quite some time, and with a running engine, it has to, I would think, over come this, as you said, many times a second. As when you test an engine, it takes time to build up the psi, couple revolutions, but it eventually builds. If a leak down test where performed and psi decreased at an irregular rate, this would be bad, something would be worn, yet your saying that in this case, the psi would decrease rapidly, im just not sure how, as either you fill the chamber with air or create a vacuum, if you shut the valves at TDC. Where am I getting lost?

 

In the time of one stoke, the rings do not leak very much, lets say one percent. In one hundred stokes enough gas leaks to equalize things. Remember that if the rings did not leak during the intake stroke, in the upward direction and with only 14.7 psi of atmospheric pressure, then the upper cylinder and compression rings would not get oiled and engines would not last so many miles. A little leakage can be a good thing.

I just did a leak-down test and, over a few seconds, quite a bit of air gets by the rings. The higher the rpm, the less gas leaks by the rings.

 

But we are talking multiple revolutions a second.


Ah forget it, Im just not gonna get the mental picture.


I understand it works, just not sure Im 100% how it works, Im 75% and thats ok with me.


Thanks man.

 

How would you stop the valves on the dead side?

 

edit......

 

The valves on the dead side are disconnected from the cam motion. The early (1981) Eaton system used solenoids that mounted above rocker ball fulcrums on the rocker stud. When energized electrically, they let the ball fulcrum and rocker rise when the pushrod pushes up, with the valve stem end of the rocker remaining at the valve-closed position. A spring kept everything loaded enough to keep all play out and return to the starting position (& also keep the lifter from pumping up). So far as I have been able to determine, this Eaton component worked the way it should.

The later systems are discussed in the links at the top of the thread, but the new Eaton approach is to do the same function in the lifter.

 

Still have my old brain rollin with thought, cant be good.

Would be interesting if someone has information that represents a "dead" cylinder, measuring internal pressures and rpm.

Another thing that occurs to me, if your working on an engine and you need to set the valves or rotate the engine for whatever reason, its always easier to turn the engine with the plugs removed. Now I would only imagine, if you completely closed four pairs of cylinder valves (in a v8), it would only become more difficult?

Now as I slowly connect the dots your laying out, your saying that initially there will be more resistance as the DOD is activated but over many revolutions the cylinder equalizes, ok, now the light buld comes on, by equalize you mean mid stroke becomes the fulcrum if you will, which is why you give the analogy of a piston at mid stroke and springs above and below....gotchya....finally you sigh in relief huh? Thanks again, learn something new everyday right?

Im really done this time.



How easy or difficult will it be for you to find the eaton parts?

 

Until I read the links yesterday, I did not know about the whole thing of pressure being neutral at mid-stroke. I read it (I think Eaton stated it) and am quite convinced that it makes sense. Previously I thought that the air just got compressed and decompressed through the whole stroke - this also means that you get all the energy back.

In your example of turning over an engine, the problem is that you are so slow that you pump the air past the rings on the compression stroke (doing work) and then on the power stroke, you pull air upward past the rings, doing more work. (Moving air is work - that is why compressors need motors!) If you have ever pulled a large one cylinder over on a crank through the compression and power strokes, you can feel the air-spring effect. Once you go rapidly through the compression, you can feel the air carrying you on the down-stroke. (All of this with no spark, of course.)

The Eaton system was used on some Cadillac cars for only 1981 and it was called the "V8-6-4" engine. It was used for 3 more years on limos (I do not know why). First I will check out the junk-yards.

 

In an earlier post in this thread, I mentioned cutting off individual injectors on a EFI 300. Of course, this is total nonsense. The only EFI Ford I worked on physically was a direct-port injection V-6, so that is what stuck in my mind. I have a friend who had a '93 F-150 and I now remember that it is throttle-body fuel injection, so what I said would NOT be possible for a factory EFI 300. For now, I am sticking with carbs.

 

If the valves were closed, your still gonna have to draw air past the rings on the compression stroke and pull air upward past the rings on the power stroke, regardless of speed, faster just means it equalizes quicker. Gotchya, I was thinking in print, when I typed my example...shoulda edited.

I guess im thinking the equalization process could be improved upon, just speculating. If the DOD could be timed per cylinder, it would be more ideal for the valves to close on the exhaust stroke, mid stroke. This would put the piston in an equalized state and avoid the transition altogether. For all I know, the equalization process is quick at cruise rpms, even if the valves shut on the intake stroke and went through the process of equalization, dunno, just speculating perfection I guess.

I understand your one cylinder analogy, what throws me off, the air cushion effect or energy release, still isnt enough to over come compression stroke, so you have resistance until momentum is created to overcome the compresson stroke along with the energy released, Im just thinking, lets get to an equalized state now and not wait...haha

I can definitely see the benefits of having the valves permanently shut vs having the valves going through normal motions, as it would constantly be trying to overcome the compression stroke, which along with momentum it might equalize as far as inertia, is that a good term? Momentum? It would still have some resistance, I imagine that was partial reason why the engineers went with closed valves, that and maintaining a certain level of ring seal and not having a false lean condition in v8's. I also realized, with an obd-II, it would throw the second O2 after the cat off, while it doesnt matter for performance other than a check engine light, it would make the vehicle ability to monitor the catalytic converters funtion impossible, a no no for emissions standards...haha

Dont misunderstand my post, Im just thinking in print, I learn better that way I guess, I re-read what I type and modify till it makes sense...to me anyway. Then let those that actually have an education correct me.

 

No, all efi 300 were direct port injection, its possible.





Since we are confessing.....my initial comment about air fuel ratio being affected by allowing the valves to be open, was suggested with a v8 in mind, more specifically, one using an O2 for each bank, as that was what the link was discussing.

 

OK, now I am really confused about one point. My friend says his (now sold) '93 was throttle-body injection. (He could be wrong.)

Were 300's throttle-body injection, or direct-port injection, or did they make them both ways? (I am still going to stick with carbs . . .)

 

All production ford efi 300s are direct port injection. They have six injectors, one on each port...then you have plenum runners that have to be 20 some inches long, connected to plenum, then you have a dual bore throttle body attached to control incoming air.

As far as, all ford trucks up to 96, they were either direct port injection or carb, no TBI (aka one or two injectors inside the actual throttle body).



I hope to see more of your concept, good luck