Working on some SBM iron heads and need to shim the valve springs about 0.100". That is too much shim to put under the valve spring to keep the spring accurately located. I'm using 3/8" stem 1 groove valves. Does anyone know of a negative height spring retainer? Comp has -0.050" locks. The Comp lock + shims would probably work fine. I'm just hoping to find negative height retainers and negative height locks to limit the amount of shims needed.
Negative Height Valve Spring Retainers
- Thread starter Earlie A
- Start date
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mygasser
Well-Known Member
couldn't you split the number of shims between under the spring at the head and above the spring at the retainer?
neil.
neil.
That is an option, but I would need to put a 0.060" shim under the retainer that has about a 0.094" step. That's cutting it a little close. To make matters worse, the shim ID is smaller than the step on the retainer, so the shim won't fit anyway. Thanks for the suggestion.
Newbomb Turk
Well-Known Member
7 or 10 degree retainers?
Newbomb Turk
Well-Known Member
I bought the wrong springs for my 273 (too short) either that or the valves were too long, but the machine shop made them work. They machined down some old retainers for shims.
I found these:
VTO, 4140 Chrome Moly Steel Retainers 10 Degree 1.437"-1.450" - Competition Products
and these:
https://www.compcams.com/super-lockstm-10-176-angle-3-8-stem-size-16-qty.html
This would give me 0.100" without shims.
So the question is this - is there any problem mixing locks and retainers from two different manufacturers?
VTO, 4140 Chrome Moly Steel Retainers 10 Degree 1.437"-1.450" - Competition Products
and these:
https://www.compcams.com/super-lockstm-10-176-angle-3-8-stem-size-16-qty.html
This would give me 0.100" without shims.
So the question is this - is there any problem mixing locks and retainers from two different manufacturers?
Newbomb Turk
Well-Known Member
There is always the issue of not getting the exact amount of change you want.
I’ve seen the .100 up stuff be as low as only .070 and I had some back in the 1990’s that were .125 up.
Other than that, it’s not usually an issue.
I'm going to have to shim some anyway. Both Chrysler's and my machining skills lead to some height differences.
TT5.9mag
Two atmospheres are better than one
Why can’t you use a thick spring locator? Howard’s had some 060 last time I looked. They may have thicker than that.
For example
COMP Cams 4713-16 COMP Cams Valve Spring Locators | Summit Racing
That’s .100 thick. The spring diameters may not work for you but they might have something that does.
For example
COMP Cams 4713-16 COMP Cams Valve Spring Locators | Summit Racing
That’s .100 thick. The spring diameters may not work for you but they might have something that does.
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The OD of the spring locator on the cast iron head is 0.994". The ID of the valve spring is 1.06". Not much room for the locator shim. If the head were machined for viton seals this would be easier.
When I switched my buddy’s heads over to LS spring package I had to cut them down for .500 seals. them I had to use negative retainers and keepers to get enough spring pressure for a .660 lift cam. .060 coil bind do we cut it close. PAC was satisfied with how they were set up.
In hindsight I should have just done the bronze guides first thing. These heads were not supposed to get this complicated, lol.
It happens. Lol
PRH
Well-Known Member
In situations like that I usually end up machining the heads for spring cups.
Then if necessary you can shim under the cup, or even inside it.
Then if necessary you can shim under the cup, or even inside it.
It happens fast, doesn't it? It's good to see you're continuing to work and learn with what you've been doing there! These Big Chevy rotator eliminators could possibly be made into some valve spring cups.
Chev BB Exhaust Rotator Eliminators, 1.732" O.D., 1.568 Spring O.D., .623" Spring I.D. Thickness .300" Set of 8 - Competition Products
PRH
Well-Known Member
Easy peasy
PRH
Well-Known Member
I don’t recall on that set, but it would have been minimal.
In the past when I was building some circle track engines, the springs we were running needed pretty tall installed heights, and I was cutting the spring pockets .050-.060” deeper.
May not have been the wisest plan, but never had one break through.
There were a few places on the ones I’m doing that now needed .015” to get the intakes evened out, as well as the exhaust evened out.
I was looking for 1.700”, and with no shims or cups the intakes were about 1.790”, and the exhaust 1.775”.
They’re getting dual springs so the heads needed to be cut anyway.
The .060” cup and one shim under it will put me right at 1.700”.
In the past when I was building some circle track engines, the springs we were running needed pretty tall installed heights, and I was cutting the spring pockets .050-.060” deeper.
May not have been the wisest plan, but never had one break through.
There were a few places on the ones I’m doing that now needed .015” to get the intakes evened out, as well as the exhaust evened out.
I was looking for 1.700”, and with no shims or cups the intakes were about 1.790”, and the exhaust 1.775”.
They’re getting dual springs so the heads needed to be cut anyway.
The .060” cup and one shim under it will put me right at 1.700”.
Dave999
Well-Known Member
Crane multi-fit retainers combined with standard or offset locks used to give you loads of options provided you didn't use a combo that causes the retainer to hit the "armpit" of the rocker
no idea if they are still made but you could get a mopar sized hole retainer, offset up or down and use appropriately sized locks for your valves that you could also get offset up or down.
no idea if anyone continues to make crane branded stuff
no idea if they are still made but you could get a mopar sized hole retainer, offset up or down and use appropriately sized locks for your valves that you could also get offset up or down.
no idea if anyone continues to make crane branded stuff
PRH
Well-Known Member
That’s not at all uncommon……..and is one of the benefits of cutting the spring pockets.
It gives you the opportunity to even them out.
You were right about the lock height variance. Just changed out Comp 612 locks (standard height) for Comp 609 locks (advertised as -0.050"). The minimum change in spring installed height was -0.071" and the maximum was -0.102". Average change was -0.087". In this case it worked out perfect because I needed about -0.100" anyway.
And within the group of 609 locks themselves the variation in installed height was at least 0.020". In other words, just changing from one pair of 609 locks to a different pair of 609 locks could change the installed height by 0.020".
I'd be extremely careful machining the spring pockets deeper. Some heads are very thin in that area.
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