Spark Plug Advice Needed

bobscuda67 said
When I set the idle mixture screws I turned them all the way in until it stumbled then turned out 1/4 turn. That seemed to help more than using a vacuum gauge.
Cut another plug open today and it's a little bit rich.
If you look down the threaded shell you can see it's black all the way down.
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That’s not a little rich. That’s very fat. These threads all run together after a while but aren’t these plugs out of an engine that is using manifold vacuum because the carb is fat?

If so, fix the carb BEFORE you start with timing. You are far enough off that it’s cause you to jack more timing in it than it needs.

Edit: I just went and looked and if you are sure you have 9.9:1 compression there is no way, no way it needs that much timing at idle with your cam.

Not even close.