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Valve spring install height= How tall the spring is

If the spring is installed too tall then you don't get the desired strength of the spring. If the spring is installed too short then you will most likely exceed the springs strength.
 
Tragic said:
ok, let me try another way

did you measure the valve opening when the camshaft pushes the valve down.

is there a differnce in the measurement.
the reasoning behind my question, is for a project of mine.

oh, you can also buy both caps from cummins.

not trying to hurt anyones feelings, thought that since this persone made a claim that there could be problems with the spring height, they would take the time to get investigate, if not then I will have to do it myself.
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There is an issue in the seat pressure of the valve due to the incorrect valve spring height.
 
ok I can see where this is going

you are making claims that there is or could be a problem, but dont have any data to back it up.

if so where is the pressure readings on the cylinder head, how far does the valves open up compared to (what ever you are comparing it to)

all I wanted was data, sounds to me that all you want to do is pick my post apart and try to bash me.
I say good day Sir.

sorry, I'm having a really bad day, I'm working on a k38 and having valve train problems, I was thinking of something on this matter to see if it would help me.
 
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Tragic said:
ok I can see where this is going

you are making claims that there is or could be a problem, but dont have any data to back it up.

if so where is the pressure readings on the cylinder head, how far does the valves open up compared to (what ever you are comparing it to)

all I wanted was data, sounds to me that all you want to do is pick my post apart and try to bash me.
I say good day Sir.
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Or we were joking around a little earlier a.k.a sense of humor... Everybody has stated a reason and an issue. You don't need to check the seat pressure to know that a spring that is more compressed has more pressure behind it. Valves will open up just the same but they just won't have as the same amount of pressure at the seat. If you buy 110 lb springs and your install height is .100" above whats recommended than its gonna be more like a 95 lb spring. If its too short it'll be like a 120 lb spring. If the springs aren't installed at the right height then the possibility of having issues is there and they will not perform like designed.

I'm not trying to be a prick but if you say the spring isn't related to the valve train then you're probably gonna catch some hell and now you say they are related. Its not an opinion here either pal. I'm telling you what I know. I don't have data because I just install it right the first time and wouldn't wanna mess with checking seat pressure on a spring installed thats too tall or one too short just for $hits and giggles.
 
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I just install it right the first time and wouldn't wanna mess with checking seat pressure on a spring installed thats too tall or one too short just for $hits and giggles.


isnt how HIGH PERFORMANCE was started.
 
Seems what he is trying to drive at is.....installed spring height is independent of the spring. The installed height would remain unchanged by the springs length, but rather by valve length, lock offset, seat depth, etc...
 
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Tragic said:
I just install it right the first time and wouldn't wanna mess with checking seat pressure on a spring installed thats too tall or one too short just for $hits and giggles.


isnt how HIGH PERFORMANCE was started.
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You are correct. When I did the spring install on my 12v and on my 6.0 I did check my seat pressure AFTER I measured to make sure I was in the recommended install height. I checked pressure to make sure they were all identical or damn near. Manufactures have tested the effects of a spring too tall or too short. The manufacturer I choose to buy all my springs, valves, locks, retainers and keepers from is a good company and they have always been good to me so I will go by what they state because they have done all the R&D so why should I have to? I'm not the manufacturer. If I did want to know what happens if I'm .100" off I would call them and I'm sure they would tell share with me what they found in their R&D
 
Tragic said:
ok I can see where this is going

you are making claims that there is or could be a problem, but dont have any data to back it up.

if so where is the pressure readings on the cylinder head, how far does the valves open up compared to (what ever you are comparing it to)

all I wanted was data, sounds to me that all you want to do is pick my post apart and try to bash me.
I say good day Sir.

sorry, I'm having a really bad day, I'm working on a k38 and having valve train problems, I was thinking of something on this matter to see if it would help me.
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The spring from the engine that was tested.

1.950" 165lb
1.900" 185lb
1.880" 190lb
1.770" 235lb
1.450" 370lb
1.250" 465lb

Example; 1.800" installed height 0.340" lobe would net ~ 0.560" without lash added. If we use the largest lash value 0.020" we would net 0.540".

1.800-0.540=1.260", compare that to the chart.
 
What's the actual problem. Is it wiping out the cam lobes? The only problem other than if the cam can't handle the pressure is coil bind.

For instance his 110lb 24v springs he gives a installed height range of 1.35-1.90. (stock is 1.40). So on a spring tester 1.380 was 109lbs seat pressure. So my cam has .360 lift times 1.38 rocker ratio is .4968. Subtract that from 1.380 equal .8832. I'm using all the spring. Now say you run a cam that only has .300 lift. You have room to play and I don't see ten more lbs or so causing problems

Just my thoughts.
 
I have springs now that I'm dealing with that are not of 5.9l, kinda having a problem with springs breaking under extreme load, im trying to figure out if the problem is from the spring because of too much tension or because of heat dissipation, or maybe because the tension on the spring is actullay causing the valve to cavitate around the valve, which inturn is causing the problem that I'm having

I work directly with engineers, any of this info would be good if someone has actully had a problem such as mine, I understand that I'm working with a larger motor at hand but the princable still stands, that is why I was asking the questions.
not trying to hurt anyones credibility behind there work, RD, or product, I'm trying to understand.

remeber some people who watch these furoms have a direct link to the product that you buy.

to illionoise (sorry if I spelled your name incorrectly) what type of camshaft our you using, is it stock, is it aftermarket, if it is after market who makes the cam, what is the rockwell test.
 
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Do you have any more info or specs on the springs? What are they made of? Some materials will get brital from heat and can break where some are brital to begin with but are extremely tough. The second of the two you would have to worry about tension. Where as the first of the two you have to worry about heat, obviously.

Another question... When do you see them break? Pretty much immediately or after a few heat cycles? What kind of application is this?
 
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this is on a 38 litter enigne

after install, the springs will break (exhaust side only) I have notice that the type of caps that Im using is lowring the spring height by only 0.100(that is why this post has peaked my interest)

I,m sure that I will have to have a metallurgy test done on the spring, but that will be a fight of its own, just trying to make sur ethat I have covered my rearend before I start calling bad springs.
 
Tragic said:
this is on a 38 litter enigne

after install, the springs will break (exhaust side only) I have notice that the type of caps that Im using is lowring the spring height by only 0.100(that is why this post has peaked my interest)

I,m sure that I will have to have a metallurgy test done on the spring, but that will be a fight of its own, just trying to make sur ethat I have covered my rearend before I start calling bad springs.
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Just sitting at idle on the first start up this happens?
 
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