Valve spring shimming..thoughts?

R

rjustman

New member
I have recently embarked on rebuilding my 12v for my 2006 fummins.I bought a set of dual,valve springs that were suppose to be installed at 1.880.after getting my head back from the machine shop and putting a installed height gauge on my springs I came up with 1.980.

Question is do I order new springs closer to the 1.980 installed height.or is it ok to shim the .100 to get my installed height to match that of the spring.I was thinking about using an inside spring locator which is .060 and shimming the last .040?

Springs are a manley or comp dual spring set up set at 155# seat at 1.880.I'm using comp steel retainer.and I'm not sure which locks I have.I wasn't given specifics on the set up from my supplier..

Thanks
 
So .100 is not to much shim..comp cams website says +- .020 is where the question arouse.I was told shimming is a very common practice,but as I was looking for spring locators and shims I ran across what comp reccommends for shims..
 
I'm no expert....I have never heard of the .020 limit.

The locator and a single .040 shim sounds perfectly reasonable though.
 
Ok..yeah I'm a rookie.and have been asking my supplier more questions than I think he bargained for so instead of driving him to the point of pulling out the short and curlies I figure I'd ask here.

Thanks for the responses
 
Would a certain lock be able to move installed height? A +or - .050 or .100 instead of a locator shim combo.or maybe a different lock and small shims instead of the locator shim combo??

I dunno how the different locks work or if there's even a lock out there that would do such a thing for these valves.just thinking out loud
 
There are different retainer and lock combos that can move the installed height. If you got everything form Comp Cams, I would give them a call.
 
I got everything from a vendor on here..I dunno what I have..I know I have comp retainers but that's only because they came in the comp package..everything else came in zip lock baggies..part numbers were wanted to keep secret.which I kinda understand,but at the same time I dunno what I have..
 
if the bead on the lock is narrower than stock and is down from the top just a bit its a comp 632 if its at the top and full width its a different lock that is harder to source the comp lock is a taller installed height. But i would shim it id rather have a thicker shim it would hold up better under the spring i would think.
 
I don't have a stock lock to compare to.I tossed them out when I ordered new stuff..but seems that the bead was a down from the top just a bit not sure exactly how far and I just looked at the 632 online but the pics are hard to see to compare.
I believe that I either have the Manley 22429 or the comp cam 930 springs..those are the closest to what little info I received..
 
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Kind of what I was thinking, but I didn't read what he read, so I didn't want to say it.
 
That is saying your installed height can be +/- .020" of spec.

So you can be from 1.860 to 1.900.
 
Ok..
I found a manley chart telling me how different installed heights affect seat pressure anyone have one for comp springs?
 
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so i want to bring this back up. ive been messing around with these valve springs. shims, locators, etc.. I decided to purchase a set of the victory vl8000 locks from haisley to see what they would do.. the current locks that I have are the comp cam 632 (I do believe after doing research, supplier didn't give me any part numbers after I ordered).
I decided to do this after I put the locks on a stem and seen that I had in the neighborhood of .033 play up and down the stem due to the bead being smaller on the lock than on the stem.after seeing that I figured id give victory a call and get some of their locks that are made for the 12v.
installed height with the comp cam locks was 1.980, that's where this thread originated me needing .100 worth of shims.
after the victory locks came in I now have an installed height of ~1.823 .now that my shim problem is fixed, how much can you cut these valve spring seats before you get into anything. ultimately id like to get to 1.880 installed height.

0902151746_zpsqnqzwyds.jpg

comp cam 632

1013151957_zpsrijfjhn8.jpg

victory vl8000
 
It changed that much from switching the locks? Why not try a different set instead of going into machining.
 
I did have a different set..i started with the 632 from comp. and with those I needed .100 worth of shims and spring locators. so before I started shimming I bought the vl800 locks. that brought my installed height to 1.823. the machining wont be anything really. can be done with a drill from my understanding and a valve spring pocket cutter from comp or howards. which I was already planning on buying to make everything even anyhow before I started adding shims, so I was on an even playing field. if that makes sense.

to answer your question. yes the locks were the only thing changed. I figured it would change due to taking the play out of the lock and stem from the 632's, and also having the bead at the top of the lock on the vl8000's instead of more towards the middle of the 632's. just didn't think it would change .160 worth lol.

EDIT: I worded the first post wrong. I wont be cutting the valve seats ill be cutting the valve spring pockets.. I can see what your talking about now regarding the machining..sorry
 
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