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Take a transfer punch the same size as the guide and punch the piston. That will get you valve centerline. Measure the valve radius from the punch mark plus .060 and see if you have room. If that still shows not enough room then have them opened up. What size valves are they?
 

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Discussion Starter #3
Take a transfer punch the same size as the guide and punch the piston. That will get you valve centerline. Measure the valve radius from the punch mark plus .060 and see if you have room. If that still shows not enough room then have them opened up. What size valves are they?
They are 2.08 and the cam is .600 lift i cut the clay and the radial clearance on the clay is paper thin I just tore them all out and took them to machine shop. I talked with my guy and said they are gonna take couple thousands off the radial on all just to be safe.
 

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How are you checking piston to valve clearance? Looking at where it’s breaking through you don’t have vertical clearance either. Are you setting valve lash, is this with a gasket, are these checking springs, is the cam degreed in and rotating the engine around? Or did you just push the valve down with the piston at tdc? Not trying to ask stupid questions, I’ve had people do weird things.
 

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Discussion Starter #5
How are you checking piston to valve clearance? Looking at where it’s breaking through you don’t have vertical clearance either. Are you setting valve lash, is this with a gasket, are these checking springs, is the cam degreed in and rotating the engine around? Or did you just push the valve down with the piston at tdc? Not trying to ask stupid questions, I’ve had people do weird things.
I did the clay method and set the head up with few bolts in used solid lifter on the number one cylinder with a headgasket I heard of decreeing cam too my machinist said that will get you a ball park if it’s gonna hit or be ok. The short block was already put together with timing gear assembled.anyways with all that being said valve compresses clay down and cut it and measure dial calipers didn’t even have a thousand of radial clearance that’s a no go in my eyes
 

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Discussion Starter #6
How are you checking piston to valve clearance? Looking at where it’s breaking through you don’t have vertical clearance either. Are you setting valve lash, is this with a gasket, are these checking springs, is the cam degreed in and rotating the engine around? Or did you just push the valve down with the piston at tdc? Not trying to ask stupid questions, I’ve had people do weird things.
I had 2 thousands on vertical guess valve relives radial wise just not big enough on those pistons I dropped pistons off at shop today with the clay on the one and they said they are gonna give it a 2 -3 thousands on the radial and it’ll be good
 
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