This has probably been explained many times before, so I apologize for taking everyone's time again. I know I have to enter the initial timing in the bin file ( in my case 12 degrees) When I look at the main spark advance tables, are the values there in addition to the initial in the distributor? If at 2400, and 80kpa, the value is 32, does that mean the actual amount of advance is 12, + 32, = 44 degrees advance? If this is so, why does the ecm need to know what the initial timing value is?

 

That would be correct! If you had the initial timing value set at 0* in the tuning and had the distributor set to 12* you would have 44* total advance in the situation you described above. However if you tell the ECM you have the distributor advanced 12* in the tuning it will automatically compensate for the distributor advance and only command 20* to reach 32* total.

Getting more advanced the distributor latency settings must match the ignition control module in use and even the factory have some timing variation to them. The 048 module retards the timing above 3,200 rpm, while the 369 advances.