Dear List:
For those of you that followed my thread concerning the correct valve timing
clearances, the usual suspects specifying .029 vs. David Vizard's .019.
I decided to take it to the Vizard himself and wrote to APT.
This is the response, which you may want to file away for future reference.
David,
Certainly it is possible that three books all give the same bad info. I
think you will also find the same incorrect picture of a distributor drive in
several books. That is why we use the method of checkin the cam at full
lift. We measure lift right off the pushrod - - no clearance. For example,
we time in our mildest cam to acheive full lift 103-104 degrees after top
dead center, measured at the #1 cylinder intake pushrod.
jack Holdaway
Now I am going to check full lift off of the pushrod.
I am scared to ask what is wrong with the picture of the distributor drive.
David Oliner
60 Bugeye
67 TR4A
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