Well, Chris...
The mechanical advance curve should
be in the (1500?) maint. manual you are
using. Fr'instance, the advance curves
are shown for the different "A" series
engines in mine and should be in whatever you are using.
The priority at this point will be the total
advance first, then the advance curve
second.
So first I would suggest setting total
advance "correctly" to the figure so specified for the basically stock
engine.
Fr'instance, this would be 32-34 degrees
on a stock (or even mildly tuned) Series
"A", assuming unleaded premium.
If this results in a sluggish bottom end
in terms of acceleration, then you have
two choices (actually 3, the third one being another more "suitable"
distributor
having a more "suitable" curve to begin
with!).
1. You "recurve" the advance curve OR,
2. you "advance" manually for reasonable acceleration, then put a "stop"
into
the distributor to prevent "over advance"
at the "top". This is what is done to stock
Lucas dizzies used in supercharged applications, wherein timing is set
to
the stock "static" setting, then total advance is limited to 24-26
degrees by
slipping a correctly sized bush over the
limiting "stop" in the dizzy, thus "tailoring"
the total advance for 100% cylinder
filling and the higher dynamic compression ratio which results from
forced induction as rpms increase and
the blower really starts putting out the
boost, while retaining the stock advance
curve or rate for the bottom end when
boost (and thus cylinder filling) is less than max or virtually
non-existant.
Obviously, a programmable timing light
comes in quite handy in all of this, as
does a distributor machine (the latter
are rare these days!).
I will forward under separate mail a
website provided by fellow lister
Mike MacLean on setting up advance
curves which hopefully, will be helpful
to you. :)
Cap'n. Bob
'60 :{)
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