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Valve Guide Clearance

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Have Acura GSR head with oem valve guides & Ferrea 6000 Valves. Checking with a split ball and outside mics. My measure valve to guide clearance is as followed (EX .0031") & (IN .0023").

Looking at Helms manual the specs are (.004"-.006") & (.009" service limit). My EX side is too tight by about (.001") approximately referring to Helms manual. Do the Helms specs seems too lose?

The ferrea valves stems i measured seems to be slightly smaller than oem valves. I would think the valve guide clearance would be looser being its old.

Checked a different GSR head and got similar measurements outcome.

You should be around 2-4 thou on the intake and 4-6 thou on the exhaust so I agree it seems your exhaust is a little tighter than it should be although I prefer to be towards the tight end of the spectrum. You could have a machine shop ream the guides to achieve the correct clearance though with minimal fuss.

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