Valvespring shims
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From: Mastic Long Island N.Y.
Valvespring shims Are valvespring (921's) shims for a stock GM head available in 10 or 15 thousandth thicknesses? Also is there a max figure for shimming assuming coilbind figures/clearances are met? I remember reading about too much shimming not allowing the spring to transfer heat. My installed heights are a bit over 1.8 (1.820) and I would like to shim to approx. 1.750 wich has me needing about 70 thous. I have 60's but would like the extra 10 or so for the extra spring pressure. Thanks in advance for replies.
Micro shim kits here:
http://www.iskycams.com/pdfcatalog/2004-05/page39.pdf
I used Isky part #6 when I did my Dart 225's and they worked like a champ. They come in .010", .015", .020", and .030"
Another option would be to use -.050 locks and fewer shims.
http://www.iskycams.com/pdfcatalog/2004-05/page39.pdf
I used Isky part #6 when I did my Dart 225's and they worked like a champ. They come in .010", .015", .020", and .030"
Another option would be to use -.050 locks and fewer shims.
Last edited by 405HP_Z06; May 27, 2009 at 09:28 PM.
All your installed heights wont be the same, and all your springs wont coil bind at the same height. Shims come in 15,30, and 60s.
I use Comp # 4753. Its a kit and there is 16 each of .015, .030, and .060 thick spring shims.
Truly setting up your springs from coil bind on an individual basis will allow the .015" increment to get you to within .005" on each without a problem.
I use Comp # 4753. Its a kit and there is 16 each of .015, .030, and .060 thick spring shims.
Truly setting up your springs from coil bind on an individual basis will allow the .015" increment to get you to within .005" on each without a problem.
Last edited by SweetS10V8; May 27, 2009 at 09:35 PM.
Thread Starter
9 Second Club
iTrader: (23)
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From: Mastic Long Island N.Y.
Should I go with one method over the other? I'm looking at 2 shims to obtain these figures would I be better off with the locks you suggested and a single thinner shim?
