Good Initial Timing and Too much Total Timing Problem. Seeking guidance to minimize total timing. 1969 Swinger 340 4 Gear

Cubzy said

Shouldn’t initial timing(12 in my case)plus mechanical timing(haven’t tested this yet)=all in timing(57 in my case) 12+mechanical timing=57deg. Therefore my mechanical timing is 45deg which would be the mechanical timing. This sounds like way to much? What am I missing?

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You DO NOT INCLUDE VACUUM ADVANCE speaking about timing. It is whatever it is when you plug the vacuum can in, UNLESS you have an adjustable vacuum can and then you can use that to tailor the vacuum advance to come in at different vacuum levels. Total timing = initial idle timing plus the mechanical advance in the distributor and DOES NOT INCLUDE the vacuum advance. The vacuum advance is ON TOP OF the total. "MOST" vacuum advance cans pull in about 20 degrees of timing, so if you're at 57 now, you are probably "around" 37 degrees total.