There's not much you can do about base circle runout. I'd say your best
bet is to set the lash when you are opposite (180 degrees from) the lobe
center, i.e. the the lobe is pointing straight down. This is what the
rule of 9's does. If you need convincing, just pick up a cam and look at
it. If that point is not on the base circle, then the cam doesn't have
one. Some of the other methods suggested do no do this, and might have
a problem for a long duration racing cam with long ramps.
If you've got an inline 6 cylinder, you need to look at the cylinders
that fire 360 degrees apart.
Larry
Randall wrote:
>Exactly. Which begs the question, what's the "right" place to set valve lash
>when the base circle isn't round ?
>
>Randall
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