I remember a couple of threads on here concerning timing advance & timing
curves, so I thought I would consult the collective wisdom.
I am starting to play with the advance curve on my mustang and when finished
and happy with the results, I will try to replicate on my tiger too.
I am about to replace the springs in the distributor to see what difference
in the advance curve I will get. So I made a chart of my initial factory
advance at various rpm's and found that I was 'all in' mechanical around
3500 rpm. Based on what I have read, I want that to be closer to 2500-3000
for better performance. I will have to see how big of a difference the
springs make.
But on to my real question, as well as checking my mechanical advance, I
also checked my vacuum advance, and found I was getting very little from the
vacuum advance. While I realize this is more about fuel economy at cruise
speed, it would be nice to get a feel for what an appropriate amount of
advance would be for the vacuum advance and at what vacuum it should be
applied at. Any guidance? I thought I remember reading once that 20
degrees of vacuum advance was about right, but that is significantly more
than the 8 degrees additional I have now at 15lbs (and more realistically,
my engine probably makes more like 12lbs of vacuum in the real world, which
would only be 5 degrees additional advance).
So what do you guys think?
Thanks,
Steve
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