Author Topic: Spring weight?  (Read 489 times)


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Spring weight?
« on: September 23, 2017, 08:40:46 AM »
What is the poppet valve compression spring weight rating on a OEM QB -79 valve?

I am sitting here with a brand new 79 valve and have a WILD out of the box Idea brewing.

While checking this valve out,
I find that the valve seating base/area is a raised conical brass ring, instead of flat faced,
that sets inside of a recessed flat type "O" ring of the poppet valve face, (sealing area).

Should I build it the same as the OEM valve seat, or change to a flat faced seat?
I plan on making a Delrin valve set/poppet for the upcoming mod build, ($200 Ninja build).

If a spring weight was say, 17#'s in compression form (pushing), during hammer stroke of 1/8 to 3/16" movement,
and you changed the spring to a lifting force of 17 #'s, (after the compression of the hammer stroke stroke),
the spring would lift the valve stem, by force) etc, would it work the same?

I think, I found springs that would work for this out of the box Idea I have.


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Re: Spring weight?
« Reply #1 on: September 23, 2017, 10:04:48 PM »
Sorry, I don't know the spring force on a QB valve, but I would think somewhere around 7-10 lbs. when on the seat....

You can leave the seat in the valve stock, just make the seat on the Delrin poppet flat....

Your question about having a spring "lift" I do not understand....

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