Help me understand these relationships please
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Help me understand these relationships please
As I mentioned in my earlier post, I am starting from a stock bin for this next tune. As I was wondering through Tuner Pro, I came across three things that I *think* are related to O/L idle in the 7747.ecu. They seem each contradict each other, so could somebody tell me how they realate
They are:
O/L AFR vs Temp...............the base for O/L AFR calculations?
Time Out AFR vs Cool-->Choke (subtracted from AFR vs Temp) .............subtracted from O/L AFR vs Temp ie. 13.00 (O/L AFR) - 3.00 (Time Out AFR) =10.00 to 1 AFR?
Cold AFR vs Kpa.........is this added to (lean) or subtracted from (richer) the value of one or both of the above values under load?
TIA!
They are:
O/L AFR vs Temp...............the base for O/L AFR calculations?
Time Out AFR vs Cool-->Choke (subtracted from AFR vs Temp) .............subtracted from O/L AFR vs Temp ie. 13.00 (O/L AFR) - 3.00 (Time Out AFR) =10.00 to 1 AFR?
Cold AFR vs Kpa.........is this added to (lean) or subtracted from (richer) the value of one or both of the above values under load?
TIA!
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
These two tables get added together to form the commanded AFR:
O/L AFR vs Temp...............the base for O/L AFR calculations?
Cold AFR vs Kpa.........is this added to (lean) or subtracted from (richer) the value of one or both of the above values under load?
This table is subtracted to enrich the AFR. It decays out over time, slower when cold, faster when warm:
Time Out AFR vs Cool-->Choke (subtracted from AFR vs Temp) .............subtracted from O/L AFR vs Temp ie. 13.00 (O/L AFR) - 3.00 (Time Out AFR) =10.00 to 1 AFR?
'747 open loop fueling. PE/WOT mode has it's own commanded AFR table. Which is compared to the open loop value and the richer of the two is selected.
RBob.
O/L AFR vs Temp...............the base for O/L AFR calculations?
Cold AFR vs Kpa.........is this added to (lean) or subtracted from (richer) the value of one or both of the above values under load?
This table is subtracted to enrich the AFR. It decays out over time, slower when cold, faster when warm:
Time Out AFR vs Cool-->Choke (subtracted from AFR vs Temp) .............subtracted from O/L AFR vs Temp ie. 13.00 (O/L AFR) - 3.00 (Time Out AFR) =10.00 to 1 AFR?
'747 open loop fueling. PE/WOT mode has it's own commanded AFR table. Which is compared to the open loop value and the richer of the two is selected.
RBob.
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