Pelican Parts Forums - 2x valve spring height questions

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valve spring height questions

Hi. I have some old shims. They are cerated. Use or stick with the new ones I have purchased.
Sixty seven 911S heads
Lyndon
http://forums.pelicanparts.com/uploa...1592812029.jpg

I would use the original shims as they are period correct for the antique value of original.
Bruce

They are old school parts from NAPA with old thinking.Better check the cc,s for compression as every time there is a valve job the compression is reduced from a stock setting.I would always clean one piston & head then cc to see what you are starting with.Adding new valve seats adds an exponential cost to the rebuild.9.3 to 1 can get to 8.2 to 1 real quick with a non Porsche shop cutting the valve seats then refacing the valve to drop it even more.A resurface of the head will gain a little back but that changes the reference of the idler shaft to the tensioner extension.Aint this fun?