Fuel tables and target AFR
#1
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Car: 1991 Firebird
Engine: LO3 5.0 TBI
Transmission: TH700R4
Fuel tables and target AFR
Can someone please clarify how the 2 fuel tables are used.
I am guessing that either as table 2 has no load/MAP axis, it is used only under high load (80-100MAP) or when above table 1's max rpm limit - 3200.
OR
Table 1 and 2 are added togethor under all conditions, above 3200 the ecu calculates based on the 3200 value in table1+the table 2 value at the present RPMs.
under WOT does the ECU calculate how much petrol to inject based on the WOT/target AFR plotted solely against the VE value in table 2
tables 1and2 added togethor
some other combo.
Thanks for any assistance.
1228746 - $61 - ANTS (modded)
I am guessing that either as table 2 has no load/MAP axis, it is used only under high load (80-100MAP) or when above table 1's max rpm limit - 3200.
OR
Table 1 and 2 are added togethor under all conditions, above 3200 the ecu calculates based on the 3200 value in table1+the table 2 value at the present RPMs.
under WOT does the ECU calculate how much petrol to inject based on the WOT/target AFR plotted solely against the VE value in table 2
tables 1and2 added togethor
some other combo.
Thanks for any assistance.
1228746 - $61 - ANTS (modded)
Last edited by Mc Firebird; 02-02-2004 at 07:34 AM.
#2
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Car: An Ol Buick
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Transmission: Janis Tranny Yank Converter
Re: Fuel tables and target AFR
Originally posted by Mc Firebird
I am guessing that either as table 2 has no load/MAP axis, it is used only under high load (80-100MAP) or when above table 1's max rpm limit - 3200.
OR
Table 1 and 2 are added togethor under all conditions, above 3200 the ecu calculates based on the 3200 value in table1+the table 2 value at the present RPMs.
under WOT does the ECU calculate how much petrol to inject based on the WOT/target AFR plotted solely against the VE value in table 2
tables 1and2 added togethor
some other combo.
I am guessing that either as table 2 has no load/MAP axis, it is used only under high load (80-100MAP) or when above table 1's max rpm limit - 3200.
OR
Table 1 and 2 are added togethor under all conditions, above 3200 the ecu calculates based on the 3200 value in table1+the table 2 value at the present RPMs.
under WOT does the ECU calculate how much petrol to inject based on the WOT/target AFR plotted solely against the VE value in table 2
tables 1and2 added togethor
some other combo.
table two is an adder.
The values in table 2 are added to those in table 1, all the time.
Table two allows for saving code space and processing time.
You'll notice the VE 2 values drop at the higher rpm, as the VE of the engine decreases.
The PE AFR is based on the two VE tables giving a Stoich AFR.
The BPC, VE1, VE2, PE AFR, all have to play nice together for it all to work.
#3
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Car: 1991 Firebird
Engine: LO3 5.0 TBI
Transmission: TH700R4
Can I ask you to clarify please, if i understand you correctly then
Scenario 1
I am cruising down the road at 1600 RPMs/40Map, the VE will therefore be
the table1 1600/40 value of "43"
+
the VE2 table adder 1600 value of "44"
giving a total VE of 87.
Scenario 2
i am pressing on, 4000RPM/80 MAP , the total VE will be
the table1 3200/80 value of "50"
+
the VE2 adder value at 4000RPM "39"
giving a total VE of 89.
As the VE1 table only goes to 3200 i am assuming the last highest value at the present MAP level is used ?
Thanks again.
Scenario 1
I am cruising down the road at 1600 RPMs/40Map, the VE will therefore be
the table1 1600/40 value of "43"
+
the VE2 table adder 1600 value of "44"
giving a total VE of 87.
Scenario 2
i am pressing on, 4000RPM/80 MAP , the total VE will be
the table1 3200/80 value of "50"
+
the VE2 adder value at 4000RPM "39"
giving a total VE of 89.
As the VE1 table only goes to 3200 i am assuming the last highest value at the present MAP level is used ?
Thanks again.
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Car: check
Engine: check
Transmission: check
Originally posted by Mc Firebird
Can I ask you to clarify please, if i understand you correctly then. . .
As the VE1 table only goes to 3200 i am assuming the last highest value at the present MAP level is used ?
Thanks again.
Can I ask you to clarify please, if i understand you correctly then. . .
As the VE1 table only goes to 3200 i am assuming the last highest value at the present MAP level is used ?
Thanks again.
RBob.
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