figuring out advance timing

You are still not getting it Mattax. The softest engagement for a TF [ or any auto going into gear from N or P ] is to have the engine making as much HP at idle speed. Stock engines do not clunk into gear with their 500-600 rpm idle because they are making enough HP at THAT rpm to sustain the engine at idle. Big cams will NOT idle at very low rpms because they are not making enough HP to sustain engine operation at idle. In this situation, giving the engine more timing at idle produces more hp & allows a lower idle rpm than it would with the factory 12* BTDC. MVA is a simple & effective way of adding the reqd timing.
This is from Mopar Muscle Oct 15

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