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Re: crank/cam timing??

To: w3ike@yahoo.com
Subject: Re: crank/cam timing??
From: "Harlan Jillson" <hjillson@argohouston.com>
Date: Mon, 10 Aug 98 10:15:31 CST
Ike,
   Finally one even I know the answer to.  What you're
checking by watching the valve lift vs. the crankshaft
timeing mark is the cam timeing.  You're indication is 
that the cam is 5 degrees advanced of the crankshaft, 
which isn't very good actually.  We used to do this check
on sprint car race engines with a dial indicator on the 
#1 intake at I believe 0.050" lift ( years ago...).  If 
your cam has been replaced with a re-ground cam it could
easily be off this much, which is why you want to index
your cam when installing.  The correction is either an
indexing cam sprocket that lets you dial in the amount of
cam advance ( very expensive), or a sprocket with oversize
mounting holes and offset bushings that let you set a 
specific amount of advance/retard based on the bushing 
offset ( the bushing come in a varity of degree offsets).
The later sound like the most appropriate fix to me.
Good luck.
Harlan.

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