Any timing you add to the initial timing (idling with the vacuum line plugged) will be additive to the total timing........the 2 degrees on the initial timing will show up on the total timing end......adding 2 degrees to the initial will result in the 38 total you now have going to 40.

You are indicating that you're checking the total timing at 3500. If the total timing is not coming in until that RPM it's a little high for a street driven engine. You make that change with either heaver mechanical advance weights OR lighter advance weight springs (both of which can be purchased in the various advance weight kits. For normal street driving the engine will likely be happier with the total advance being all in at around 24-2500 RPM.


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