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valve springs I am rebuilding the engine from my 1940 pickup. I have read several of the recommended books and many threads on here. I am going to run a Schneider 254F cam with .355 lift. My assembled valve spring height ended up right at 2 inches. I measured spring pressure using Ron’s method on the new springs (sealed power) that were provided by the machine shop. The pressure at assembled height is just below 30lbs. If I add 2 .060 shims I am right at 50 lbs. seat pressure. Should I use these springs and shim or try a different spring? I am a little concerned that new springs need to be shimmed that much to get to 50LBS seat pressure.
Thanks Phoneman |
Re: valve springs I would use different springs. Lincoln Zephyr springs work really well. Readily available.
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Re: valve springs Quote:
They are a "progressive" wound spring and work really well. Thanks, Gary in N.Y. P.S. Not all that familiar with the '40 units but if it is the same (basically) guide setup as the 8BA you may have an issue "stacking" numerous shims on there, you MAY not have enough height on the spring registers?? |
Re: valve springs I need to check my notes, but I believe the LZ springs I purchased from Red's were at 50# @ 2.125. I will check them at 2" and see what I get for reference.
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Re: valve springs Gofast
The Sealed Power springs I have are VS-392. If yours are the same and test good I may need to run back by the machine shop and use a more accurate tester. I appreciate everyone's thoughts on this. Phoneman |
Re: valve springs You can run 2 vsi one at each end :)
R |
Re: valve springs That does sound low, but the 2" sounds long. are these chevy valves??
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Re: valve springs 1 Attachment(s)
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Thanks, Gary in N.Y. P.S. Would not care to use shims top & bottom, but that's just me. With the 393's (in the photo on the right side) you'll likely need no shims if your measurements are correct! |
Re: valve springs Sounds like the springs are to short, 2 .060 spacers may make coil bind. Walt
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Re: valve springs You need about 60 lbs at 2.00 installed height. Depending on which valves and retainers you have, you may be too long and need shims to get down to 2.00. I'd try to get to 55 to 60 lbs on the seat with that cam . . . you shouldn't need more than that. The correct 'LZ' type springs should work - I think the last set I bought came from 'Reds Headers'.
Good luck, B&S |
Re: valve springs The valves are 8ba replacement valves. I did a little looking on the sealed power web site. The VS-392 is a spring for 52-53 flathead V8 and is 2.200 free height. where the VS-393 mentioned is listed 49-51 and is 2.480 free height. It looks like I was supplied the springs for rotators. Thanks for everyone's help.
Braden |
Re: valve springs I believe the Ford unassembled height at rest is 2.41" with 11.5 coils wire Dia.approx. 0.140", Ford says to change them out if they are 0.125" shorter. This is the 40 stock valve spring 78-6513
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Re: valve springs Quote:
Good job you checked! Just a note on the Schneider cam. Pay real good attention to the ignition drive slot in the front, and confirm its placing against the stock cam. They can be off line, Mart had this issue recently, think it buggerd up the ignition bushings. He did resolve the issue on his without changing the cam (being in England, sending it back for sorting by Schneider is cost and time prohibited) I can't remember how he did it, but it's here on a thread someplace. Martin. |
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Re: valve springs The cam I have has the slot offset but by a smaller than correct amount. I made a one off shaft to match by welding and filing the tangs to engage with the incorrect offset.
Mart. |
Re: valve springs Dale,
wrote a reply, but Mart has already answered. Thanks Mart. Martin. |
Re: valve springs Scooder
Thanks for the heads up on the possible issue with the cam. Mine looks like its fine. This is my first flathead rebuild so I am double checking everything. Braden |
Re: valve springs Quote:
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Re: valve springs It was a new one from Schneider.
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