I am looking at the 454 spark map on a 2000 for the C3500 truck, mainly as a guide to my 99 K2500 454 Suburban (anyone have a OEM for this truck?).
Ok, there is the Optimal Timing Map (B1040), and then the Main Spark Advance (B5913), and then the ECT (B5910) and IAT (B5911) tables.
How is the Optimal timing map (B1040) used? From what I gather the Main Spark Adv map is the timing used, and the add/subtractions come from the other tables as needed. OR is the OTM the main one used?
I never see anywhere close to the timing on the OTM. Even mine is tuned by Jesse, (not sure what he programmed in) and timing seems quite low under power.
I would expect more like 32-36 degrees at WOT, but I see in the teens.
Is there any place I can do some more reading on how the timing is determined from the maps to actual?