AFR slowly richens at idle

[Hysteric]

Cam has 46 degrees overlap exactly. I can't run less advance, its already a comprimise from 36. As stated in my initial post, the lowest rpm drop is with 13.2-13.4 in park and 14.0-14.2 in gear. I decided to get new converter, something that will be future proof, went with dynamic 9" 4800 stall witch mechanical diode. My old converer was not nitrous ready anyway. I will update whats the situation after I get parts. Since I'm in Europe, its probably going to take some time.

Overlap is calculated from seat to seat not at 0.050.
Magnum 262/262 Solid Roller Cam (3 Bolt) for Chrysler 383-440
This solid roller from Comp has 88 seat to seat and 42 at 0.050 degrees of overlap.

Forget AFR's when trying to set up your tune. You need to richen it to lower your timing.

1250ish in Park and 950ish in gear.

That's a big drop in rpm. You have to richen it up to get it to hold a load.