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Old 10-20-2019, 05:06 PM   #1
chambies
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Default Valve spring issues

I recently purchased a new set of modern valves and springs from a reputable company. I installed them for a short duration then removed them because I needed to do some head work prior to moving on. I am now ready to install when I noticed that one spring is shorter than the others by about 0.25 in... I would imagine that this difference will cause a difference in spring pressure compared to the others. I have a mild cam so Iím looking for a 60# pressure. No access to spring tester so I may set up the bathroom scale. Just wondering if anyone has encountered this? I donít like the fact that they are different lengths. I may have to purchase a new set or find some v8 springs with spacers. Thanks!
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Old 10-20-2019, 06:24 PM   #2
Russ/40
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Default Re: Valve spring issues

That is a big difference. 1/4" is a lot for springs. Why are you talking V8 valves and springs? Posting in the wrong board?
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Old 10-20-2019, 06:29 PM   #3
Railcarmover
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Default Re: Valve spring issues

V8 springs are used in A engines,the increased tension helps raise engine max rpm.Is this and OHV conversion?
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Old 10-20-2019, 10:29 PM   #4
chambies
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Default Re: Valve spring issues

Iím running standard head... no OHV. Larger intakes, dual 97ís and mild cam. Should be around 6.25:1 compression. I agree that the shorter spring is a big deal... it really caught my eye. Still need to measure lbs but I know it canít be the same as the others. Maybe will order a set from Snyderís and add spacers for a little extra poundage.
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Old 10-20-2019, 11:25 PM   #5
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Default Re: Valve spring issues

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Originally Posted by chambies View Post
I recently purchased a new set of modern valves and springs from a reputable company. I installed them for a short duration then removed them because I needed to do some head work prior to moving on. I am now ready to install when I noticed that one spring is shorter than the others by about 0.25 in... I would imagine that this difference will cause a difference in spring pressure compared to the others. I have a mild cam so Iím looking for a 60# pressure. No access to spring tester so I may set up the bathroom scale. Just wondering if anyone has encountered this? I donít like the fact that they are different lengths. I may have to purchase a new set or find some v8 springs with spacers. Thanks!
Do not even bother measuring those springs. They have 2 strikes against them right out of the box.

Go ahead and set up your bathroom scale on your drill press. You will need it to check the springs you finally use. 60 lb. will be fine for street use with most any cam.

Changing to V8 or any other springs can bring it's simple rewards such as dampers or it can be a nightmare having to make spring seats, regroove valves and buy different retainers. If you are not familiar with changing spring sizes, stick with stock replacements and shim them if they will go to 60. Be sure to check each spring for coil bind when installed.
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Old 10-21-2019, 08:57 AM   #6
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Default Re: Valve spring issues

People say 60# but what amount of compression does that mean? Is that pushed down 1/4 of an inch or 1/2 or what? Jack
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Old 10-21-2019, 09:14 AM   #7
chambies
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Default Re: Valve spring issues

I guess I need to install one and see what the installed height is with the new modern valve. Then check poundage at that length.
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Old 10-21-2019, 09:53 AM   #8
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Default Re: Valve spring issues

Les Andrew's book says compressed length is 2.250"
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Old 10-21-2019, 10:01 AM   #9
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Default Re: Valve spring issues

To get length of needed to measure spring pressure; Install valve with keeper, turn the cam so the valve is all the way open and measure the distance between the keeper and roof of the valve chamber were the valve seats, do the same when cam is heel and valve is closed. There are two different values; valve closed and valve open so you need to know which that 60# is.
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Old 10-21-2019, 12:59 PM   #10
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Default Re: Valve spring issues

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People say 60# but what amount of compression does that mean? Is that pushed down 1/4 of an inch or 1/2 or what? Jack
60 lb. on the seat.
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Old 10-21-2019, 01:14 PM   #11
chambies
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Default Re: Valve spring issues

Good info guys.... so should I measure poundage by the Les Andrews measurement of 2.25 installed height? Should be 60lbs for a mild cam. Shim if needed, then check for coil bind? Sound correct?
Thanks in advance!
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Old 10-21-2019, 01:33 PM   #12
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Default Re: Valve spring issues

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Originally Posted by chambies View Post
Good info guys.... so should I measure poundage by the Les Andrews measurement of 2.25 installed height? Should be 60lbs for a mild cam. Shim if needed, then check for coil bind? Sound correct?
Thanks in advance!
The install height will be the measurement taken when the scale reads 60 lb.
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Old 10-21-2019, 01:35 PM   #13
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Default Re: Valve spring issues

They were very likely all the same height when you put them in. If that is so, the short spring has taken a set. It probably has brothers and sisters in your engine. Scary thought.
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Old 10-21-2019, 06:57 PM   #14
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Default Re: Valve spring issues

This is a sign of poor heat treatment of the springs and or materials.

You can test the rest of them, but honestly if one has sagged this soon, others will also.

Sets of springs are not that expensive, the Isky V8 springs (gray color) I recall are 85# seat pressure and will probably handle the extra weight of the larger valves and higher operating speeds. Afterall, more compression, dual carbs and cam, you are going to rev it!!

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Old 10-23-2019, 11:22 AM   #15
Jim Brierley
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Default Re: Valve spring issues

I recently bought a set of springs from Arizona Model A, they were stiffer than other A springs I have seen or measured, about 70# on the seat, from my memory. I was looking for 60# and they exceeded that by a small amount.
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