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12-08-2018, 12:30 AM | #1 |
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math class needed on valve springs
what is the math formula for a known spring rate to calculate seat and open pressure ?
spring rate is 370lbs @ 1.00" closed valve spring installed heigh1.780 open valve spring height 2.237 seat pressure ? open pressure ? thanks in advance |
12-08-2018, 02:21 AM | #2 |
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Re: math class needed on valve springs
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12-08-2018, 09:57 AM | #3 | |
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Re: math class needed on valve springs
Quote:
370 rate x .543" lift = 200.91 lbs more than whatever you set/start with the installed height at. You have to have a baseline height/pressure to calculate from, which the spring chart or actual test pressure will provide. That height is a variable based on valve stem length, +/std./- locks & retainers, spring seat machine work, depth of valve job seats.
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LOCOMOTION Racing Last edited by Myron Piatek; 12-08-2018 at 10:03 AM. |
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12-08-2018, 11:00 AM | #4 |
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Re: math class needed on valve springs
If you can afford it, this is the cats meow..............
https://www.summitracing.com/parts/l...+5ba26a96cdb6b Wish I had it years ago! |
12-08-2018, 01:43 PM | #5 |
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Re: math class needed on valve springs
What is the valve lift on the int. and exh.?. gsa612
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12-08-2018, 04:59 PM | #6 |
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Re: math class needed on valve springs
If you can find a comparable spring on the PAC Racing site, this link to their spring rate calculator might help.
https://www.racingsprings.com/index..../?sku=PAC-1224 Edit: Change the part number to your match.
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Dale Shearon 68 Mustang 6394 |
12-08-2018, 06:08 PM | #7 |
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Re: math class needed on valve springs
The basic formula is F=kX . F is the force , k is the rate , X is the difference in spring height from the length of the spring when it is not loaded .
Last edited by ss3011; 12-08-2018 at 06:09 PM. Reason: Clarify |
12-09-2018, 12:29 AM | #8 |
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Re: math class needed on valve springs
Is the spring rate 370lbs per inch? Is the installed height 1.780? Open height can't be more than closed, what is the free height of the spring?
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12-09-2018, 11:47 AM | #9 | |
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Re: math class needed on valve springs
Quote:
To add to above, the spring rate is stated as the force generated per unit of compression. Ex: 1,000 Lbf/Inch, 1,700 N/cm etc. Also, its spring FORCE, not pressure. Spring pressure is a common misnomer racers seem to always use, and it just wont die. Its entirely wrong. Its not a pressure, Its a force. |
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12-09-2018, 10:11 PM | #10 |
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Re: math class needed on valve springs
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