A real high power SS valve maybe?



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Offline PakProtector

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A real high power SS valve maybe?
« on: January 01, 2019, 10:06:18 PM »
So, I had to look inside one. Took some measurements( it is a .250 exhaust model ). The throat area is smaller than the exhaust. It is even smaller than the standard valve that my Flex came with( and that was supposed to be the biggest). It is easy to open...:) How about a PEEK poppet with something like a .300 throat? Even .290 is easy to open...and likely tolerant of Delrin homopolymer poppets. Would be really nice to have bore area porting available for a .30 cal I can tell you that. With how fast that valve seems to close up, I could see some nice efficiency numbers I bet.
Thanks!
Douglas
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Offline Motorhead

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Re: A real high power SS valve maybe?
« Reply #1 on: January 02, 2019, 02:57:09 AM »
Odd ... my SS valve has a .280" throat with .250" transfer using .125" stem .... areas are nearly balanced.
Been using PEEK poppet w/o any sealing issues.  Note: 10* negative face cut on sealing face moving the sealing margin to extreme O.D. edge
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Offline PakProtector

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Re: A real high power SS valve maybe?
« Reply #2 on: January 02, 2019, 05:28:54 AM »
Odd ... my SS valve has a .280" throat with .250" transfer using .125" stem .... areas are nearly balanced.
Been using PEEK poppet w/o any sealing issues.  Note: 10* negative face cut on sealing face moving the sealing margin to extreme O.D. edge

Well Scott, by now you should have seen that a 90-degree exhaust port works much better when its area is smaller than that of the throat( as in the MRod valves, and these balanced we're talking about).
cheers,
Douglas
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Re: A real high power SS valve maybe?
« Reply #3 on: January 02, 2019, 12:51:32 PM »
I thought the exhaust port in an SS Valve was angled slightly towards the throat, no?.... I like to see the throat have an area (once the stem is deducted) the same as a hole about 5-10% larger than the exhaust port.... For a 0.250" exhaust port and a 1/8" stem, I would make the throat about 19/64" (0.297"). Even 5/16" is not too large for a .257 cal exhaust port, IMO....

Of course that requires a larger poppet, and increases the hammer strike required.... but would not be a problem for a balanced valve to handle....

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Offline PakProtector

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Re: A real high power SS valve maybe?
« Reply #4 on: January 02, 2019, 02:55:11 PM »
I thought the exhaust port in an SS Valve was angled slightly towards the throat, no?.... I like to see the throat have an area (once the stem is deducted) the same as a hole about 5-10% larger than the exhaust port.... For a 0.250" exhaust port and a 1/8" stem, I would make the throat about 19/64" (0.297"). Even 5/16" is not too large for a .257 cal exhaust port, IMO....

Of course that requires a larger poppet, and increases the hammer strike required.... but would not be a problem for a balanced valve to handle....

Bob

No, they are at 90 degrees; exhaust bore is radial to the axis of the poppet.

With a .3125 throat, a poppet of .37 is needed for the same .030in^2 seat area...and of course with the rest of the stock SS diameters, seat pressure goes up, so PEEK will be required I think. It will also take the valve body throat area-poppet area down to 130% of the throat-stem area as the SS valves are not bored behind the breech hold-down screw restriction( I measured mine at about .55" ). Keeping the thimble out of this will of course be useful as that is bigger than .35 of the current poppet OD. The poppet seat is ov course well below the end of the thimble, so a poppet bulge should be no issue.
cheers,
Douglas

angled throat + bigger throat + PEEK poppet = mo' muzzle energy....check is waiting :)
  • Ann Arbor, MI, USA
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Offline PakProtector

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Re: A real high power SS valve maybe?
« Reply #5 on: January 08, 2019, 06:11:10 PM »
Thanks for the discussion y'all...disappointed to see no vendor interest or acknowledgement. Guess we'll have to do this ourselves...:)
cheers,
Dougals
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Re: A real high power SS valve maybe?
« Reply #6 on: January 08, 2019, 06:14:14 PM »
Thanks for the discussion y'all...disappointed to see no vendor interest or acknowledgement. Guess we'll have to do this ourselves...:)
cheers,
Dougals
Were developing a new valve and will share information in due time but dont let that stop you from your en-devours
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