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Member - AMC/Rambler "guru"
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From what I read the camshaft has no control over the valve at all -- just cylinder pressure. I've seen very old (WWI -- 1915-18!) aircraft engines that used a similar intake valve, but without the floating seat. The intake valve is held seated by a spring just strong enough to hold it against the seat. Any time there is a vacuum created in the cylinder the valve will open. The old engines have one rocker and pushrod to control the exhaust valve. If the exhaust valve closes and the piston is on the way down, there will be vacuum and the intake valve opens -- and stays open as long as there is enough vacuum to overcome the spring. On the power stroke there is enough pressure inside the cylinder to keep the intake valve closed, so it won't come open then. This might be okay for stock engines, but there is NO overlap. Maybe I'm reading something wrong though. The only other way I can see this working would be to have a custom ground cam with a light spring. The cam would have a low ramp, just enough to provide whatever overlap was desired, with most of the "lift" being provided by cylinder vacuum. Otherwise valve train would be lighter -- remove the intake rocker and pushrod altogether. How would that affect the lifter though? A dummy or plug for the lifter hole?
 

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Chasing dreams with a ball bat
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farna said:
This might be okay for stock engines, but there is NO overlap.
Here's a thought from my pea brain. With the exhaust gas inertia pulling moving through the header pipe, and the piston slowing to a brief stop, I would think the valve would open immediately to allow some air to be pulled in, the exhaust would then be shut and the piston descending and keep drawing more air/fuel into the cylinder. That should account for the necessary overlap to make high RPM operation possible. You wouldn't want move overlap than that I wouldn't think.

Sounds to me like the valve will stay open as long as there is "vacuum" pulling it open. At the point of pressure equilibrium, the valve closes - which is perfect valve timing, also the point of making the most torque in the powerband (maximum VE).

What baffles me is the .160" of lift. WTH? How can flow enough to satisfy any type of demand? :confused:

Also, I dont' think you woudl run any valvetrain on the intake side. Plug the lifter bores or whatever. No cam action is needed.

Boy, how would you model that in Engine Analyzer???? Guess the program is not geared that way.

On a side note, I'd like to see a program that coudl calculate the "perfect" valve timing for different RPM's on a given motor - then you could "pick" where you wanted the torque etc, or max horsepower at whatever RPM would make it the most efficient.
 

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I put up the tools against$300
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I don't know if my understanding of this is correct. Does the valve actually remain stationary, yet in an open position, the air and fuel being let in through some sort of check valve that closes on the compression and exhaust stroke. What keeps it from opening on the power stroke,cylinder pressure from the combusting fuel?
 

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Troll Hunter
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farna said:
From what I read the camshaft has no control over the valve at all -- just cylinder pressure. I've seen very old (WWI -- 1915-18!) aircraft engines that used a similar intake valve, but without the floating seat. The intake valve is held seated by a spring just strong enough to hold it against the seat.QUOTE]

Yeah, I'll let someone else plunk down the bucks and play with it. I've played with them for years...in antique stationary engines, been there done that. I always thought it was a cute idea, but one of the factors that made it great for a stationary working engine will likely be the downfall in an automotive application. The vacuum draw of the intake valve is also a simple and effective governor. . One of the reasons it idles down to 300, is probably because it has a pretty limited rpm range. Do a search for antique stationary engines and you will see that it is as old as the internal combustion engine and there is a reason it was never used in and auto...and it isn't metallurgy. With such a soft spring, and it has to be in order for piston vacuum to open it, the valve action is so slow that the piston will start whacking it as speed gets to high. One of the reasons strong springs are used on radical cams is not that the springs need to close the valve, any spring will close one, it's that it needs to close FASTER as the speed increases. Valve float is the governor, and this spells GOVERNOR loud and clear. Now if you want a 300 to say 1500 rpm engine with a 1:1 rear gear it may have some application....but....
 

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omnivalves.com

Blazin72 said:
Looks and sounds like a check valve in terms of its operation. Seems like it would add a lot of weight to the valvetrain.
WEIGHT SOUNDS LIKE A GOOD ISSUE TO TACKLE FIRST. OMNIVALVES COULD HAVE SOME ADDITIONAL WIGHT AT THE HEAD OF THE VALVE DEPENDING ON HOW MUCH OVERLAP TRAVEL YOU DESIRE OUT OF THE VALVE. HOWEVER THE ADVANTAGES OF THE VALVE FAR OUT WAY ANY ADDITIONAL WEIGHT YOU MIGHT SEE.LIKE ANYTHING ELSE IN LIFE,YOU HAVE A CHOICE AS TO WHAT YOU WANT THIS VALVE TO DO.CHECK OUT OUR WEBB SIGHT AND IF THAT WON'T ANSWER YOUR QUESTIONS THEN I WILL GET INTO IT WITH YOU FURTHER. THANKS OMNIVALVES.COM
 

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omnivalves.com

woodz428 said:
farna said:
From what I read the camshaft has no control over the valve at all -- just cylinder pressure. I've seen very old (WWI -- 1915-18!) aircraft engines that used a similar intake valve, but without the floating seat. The intake valve is held seated by a spring just strong enough to hold it against the seat.QUOTE]

Yeah, I'll let someone else plunk down the bucks and play with it. I've played with them for years...in antique stationary engines, been there done that. I always thought it was a cute idea, but one of the factors that made it great for a stationary working engine will likely be the downfall in an automotive application. The vacuum draw of the intake valve is also a simple and effective governor. . One of the reasons it idles down to 300, is probably because it has a pretty limited rpm range. Do a search for antique stationary engines and you will see that it is as old as the internal combustion engine and there is a reason it was never used in and auto...and it isn't metallurgy. With such a soft spring, and it has to be in order for piston vacuum to open it, the valve action is so slow that the piston will start whacking it as speed gets to high. One of the reasons strong springs are used on radical cams is not that the springs need to close the valve, any spring will close one, it's that it needs to close FASTER as the speed increases. Valve float is the governor, and this spells GOVERNOR loud and clear. Now if you want a 300 to say 1500 rpm engine with a 1:1 rear gear it may have some application....but....
Woodz, i love to see someone using there brain out there but you have us pegged wrong in this case. Trust me you will have to have one of these valves in your hand to be able to understand it.There is no prior art in the history of man that compares to the Omnivalves.com technology.RPM has no effect on the valve we are able to make motors idle at 300 rpm because the valve makes so much torque down low.In a nut shell you can now build a motor as big and crazy as you like on the top end and our valve will make your drag car idle like a kitten and you can throw away your torque converter wile the valve delivers gob's of torque up 3500rpm. now the name of the game is to just make the motor breath,far less need to tune intake runners to exhaust pipes for scavenging and riding pulse waves when you truly have variable valve timing.Please check out our sight and get back to me. omnivalves.com
 

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Omnivalves.com

hotrodf1 said:
Here's a thought from my pea brain. With the exhaust gas inertia pulling moving through the header pipe, and the piston slowing to a brief stop, I would think the valve would open immediately to allow some air to be pulled in, the exhaust would then be shut and the piston descending and keep drawing more air/fuel into the cylinder. That should account for the necessary overlap to make high RPM operation possible. You wouldn't want move overlap than that I wouldn't think.

Sounds to me like the valve will stay open as long as there is "vacuum" pulling it open. At the point of pressure equilibrium, the valve closes - which is perfect valve timing, also the point of making the most torque in the powerband (maximum VE).

What baffles me is the .160" of lift. WTH? How can flow enough to satisfy any type of demand? :confused:

Also, I dont' think you woudl run any valvetrain on the intake side. Plug the lifter bores or whatever. No cam action is needed.

Boy, how would you model that in Engine Analyzer???? Guess the program is not geared that way.

On a side note, I'd like to see a program that coudl calculate the "perfect" valve timing for different RPM's on a given motor - then you could "pick" where you wanted the torque etc, or max horsepower at whatever RPM would make it the most efficient.
PEE brain- I like that said one pee to the other.The Omni valve still moves up and down with a standard cam,however the floating seat on my valve has >160 thousands free movement on its own.I can make that seat move .250 if I wanted to but as I say Babbie steps for now.So as you can see you still get your full lift from your cam but the floating ring seat can close back-wards to seal off openings or ports very quickly when needed due to reversions that are not wanted.This reversion happens from exhaust to intake valve overlap and it happens on compression and we call that compression overlap.It would be a small book if i had to explain all the effects that are stopped or started from this valve but as you lay awake at night it will all start to come to you and you are going to call me at three in the morning and say Holy cow batman how did your pee mind ever think of this !!! Merry X-mas
 
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