As a rule, about 30 degrees total advance is right for naturally aspirated
engines. To set it, you set timing at about 3500rpm, which can be a little
unnerving the first few times. Then you let the idle values fall back where
they may, and deal with optimizing the advance curve and bottom end.
To optimize base idle timing, use a vacuum gauge. Plumb it into the manifold
and adjust timing until you obtain the peak vacuum. Then you deal with
optimizing the advance curve and full advance.
In all cases, you also listen for ping/knock once your on the road. Put it in
third gear at 1500 rpm and floor it. Listen closely as the engine winds up.
If it's going to knock, it'll probably do it between 2-3000 rpm. If you hear
it, back off the timing until you don't. If the engine has a loud exhaust,
back it off a few more degrees once you don't hear it because it's probably
still pinging a bit.
With an engine configured the way yours is, I'd disconnect the vacuum
advance/retard and lock the plate in place, running just centrifugal advance.
I've only had few engines that had vacuum advance, and never found it to be
particularly beneficial, especially if the engine was at all warmed over.
>>> "Bowen, Patrick" <pbowen@intellinetics.com> 02/13/02 04:34PM >>>
However, I don't have a stock setup and am slightly lost on where to set up the
timing.
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