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Discussion Starter #1
I've been searching the forums for days trying to find a thread about checkiing piston to valve clearance with a dial indicator. I'm going to degree my cams for less overlap and want to verify the clearance. I know you just press down the tappet till the valve touches the piston, but is that with the valve at full lift or somewhere else? How much clearance is required?
 

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drag racer
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would the difference in rpm limit be ok with .080? or would it matter?
 

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Autobanmod
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Some have put some layer of plasticine on top of the piston crown, assembeled the heads and cam chains, turned the engine a couple of times by hand, take heads off and voila.
 

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I checked mine with playdo on the top of the piston. I have .080" and read (or was advised) on the forum that is about as tight as you want to see.
 

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drag racer
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Some have put some layer of plasticine on top of the piston crown, assembeled the heads and cam chains, turned the engine a couple of times by hand, take heads off and voila.
thats how i done it with car engines but i used silly putty because thats what i had on hand.
 

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Killer Service Inc.
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What size cams?
 

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Discussion Starter #9 (Edited)
They are stock cams. I'm doing a DIY turbo and wanted to stop the blow through caused by overlap. I should add I'm looking at the same lobe center as some turbo cams I've see, or the SE cams. Nothing real drastic
 

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the intake valve is closest to the piston about 15 to 18 degrees atdc and the exhaust is closest around 15 to 18 degrees btdc.. you could go slightly tighter clearance than .080 on the intake but .080 is touchy on the exhaust..the clay method works well. i usually trial assemble the motor with light springs in place of the normal valve springs and use the dial indicator to measure valve drop to verify valve to piston clearance..
 

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Discussion Starter #11
the intake valve is closest to the piston about 15 to 18 degrees atdc and the exhaust is closest around 15 to 18 degrees btdc.
Thank you, that is what I was looking for.
 
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