Need to lower A/F ratio across the board
#1
Need to lower A/F ratio across the board
Help just finished F/I install. Current tune has put a/f at 11.1-11.4 across the board. Looking for a good way to bring it up to about 11.7 What would be the best was to get that point? Rasing IFR or uping the VE table. If I go with the VE, let me see if I have this correct higher limits reduces fuel, so if I were to multiply the whole table by a giving point, at a time to see were it would fall, ie.102% 103% ect.
Any info would be great, Thanks
Any info would be great, Thanks
#2
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Originally Posted by 618HAWK
Help just finished F/I install. Current tune has put a/f at 11.1-11.4 across the board. Looking for a good way to bring it up to about 11.7 What would be the best was to get that point? Rasing IFR or uping the VE table. If I go with the VE, let me see if I have this correct higher limits reduces fuel, so if I were to multiply the whole table by a giving point, at a time to see were it would fall, ie.102% 103% ect.
Any info would be great, Thanks
Any info would be great, Thanks
#3
Ok I see not to mess with the IFR. I think I have them set for the correct size 42#s and ifr started at 5.29 and sacled them up from there, that is why I tought I might need to rescale them, not real sure if rate is correct. Here is what I have when at WOT a/f is around 11.1 5600-5800 7psi (Note I am runing a DYNO JET WIDE BAND) reacts correcrtly at all other points of rpm range LTFS are also (0) or below at WOT. Just a/f is out of wack-to rich at WOT. Looking for a way to bring it up.
Must have been wrong need to decrease value in VE table to lower?
Must have been wrong need to decrease value in VE table to lower?
#6
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commanded air fuel, what air fuel ratio the comptuer is trying to command, it is a pid available in the various scanners. It is a combination of PE COT and various other parameters that can influence it.
You can't properly tune a vehicle without knowing what the commanded air fuel ratio is. If your don't know the air fuel ratio your commanding, then you can't adjust the air fuel ratio your seeing, to get them to be the same.
You can't properly tune a vehicle without knowing what the commanded air fuel ratio is. If your don't know the air fuel ratio your commanding, then you can't adjust the air fuel ratio your seeing, to get them to be the same.
#7
Originally Posted by slow
commanded air fuel, what air fuel ratio the comptuer is trying to command, it is a pid available in the various scanners. It is a combination of PE COT and various other parameters that can influence it.
You can't properly tune a vehicle without knowing what the commanded air fuel ratio is. If your don't know the air fuel ratio your commanding, then you can't adjust the air fuel ratio your seeing, to get them to be the same.
You can't properly tune a vehicle without knowing what the commanded air fuel ratio is. If your don't know the air fuel ratio your commanding, then you can't adjust the air fuel ratio your seeing, to get them to be the same.
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#9
From what the a/f was on the dyno and my wide band it is a flat line and a constant 11.3-4 at wot. IFR is set @5.29. At all other driving and runing point a/f is working as it should 14.7, acting as it should. So if the IFR is good should I just scale down those cells for the rpm range at which I were rich? Say map cells 80-105 across.
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BTW, if you have your MAF plugged in it won't matter what you do to the VE for WOT fueling ranges. Do you not have a WOT fuel multiplier table of sorts? I would say leave everything else alone, and lean that out. You need to find out what, why, and where you are commanding certain AFRs.
At part throttle you will ALWAYS be at 14.7 so don't think this is all gravy, whether or not your fueling is inline, the PCM will make corrections to move you to stoich. What are you commanding at WOT? We can see that you are producing rich at WOT, but you gotta know what you are commanding to determine what direction to go in.
At part throttle you will ALWAYS be at 14.7 so don't think this is all gravy, whether or not your fueling is inline, the PCM will make corrections to move you to stoich. What are you commanding at WOT? We can see that you are producing rich at WOT, but you gotta know what you are commanding to determine what direction to go in.
#11
Here see if this makes any sence. Looking at the Fuel Air Multiplier tab I see a decrease in cell value of with in the 20kpa-45kpa/temp 100-110. (1.020 vs.0950)
Would this be in about the right cell area fow WOT??? Tab is called OPEN LOOP F/A.
I compared this to another tune of a F/I camaro with same mods and setup. This was the only part of the table that was out, seems strange. Even 3D graphs are the same except for just these few cells.
Please correct me if I am wrong.
At wot you are no longer in closed loop, now in open loop because the computer dose not care about stoich at that point, correct.???
Would this be in about the right cell area fow WOT??? Tab is called OPEN LOOP F/A.
I compared this to another tune of a F/I camaro with same mods and setup. This was the only part of the table that was out, seems strange. Even 3D graphs are the same except for just these few cells.
Please correct me if I am wrong.
At wot you are no longer in closed loop, now in open loop because the computer dose not care about stoich at that point, correct.???
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Originally Posted by 618HAWK
Here see if this makes any sence. Looking at the Fuel Air Multiplier tab I see a decrease in cell value of with in the 20kpa-45kpa/temp 100-110. (1.020 vs.0950)
Would this be in about the right cell area fow WOT??? Tab is called OPEN LOOP F/A.
I compared this to another tune of a F/I camaro with same mods and setup. This was the only part of the table that was out, seems strange. Even 3D graphs are the same except for just these few cells.
Please correct me if I am wrong.
At wot you are no longer in closed loop, now in open loop because the computer dose not care about stoich at that point, correct.???
Would this be in about the right cell area fow WOT??? Tab is called OPEN LOOP F/A.
I compared this to another tune of a F/I camaro with same mods and setup. This was the only part of the table that was out, seems strange. Even 3D graphs are the same except for just these few cells.
Please correct me if I am wrong.
At wot you are no longer in closed loop, now in open loop because the computer dose not care about stoich at that point, correct.???
#13
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Originally Posted by 618HAWK
Help just finished F/I install. Current tune has put a/f at 11.1-11.4 across the board. Looking for a good way to bring it up to about 11.7 What would be the best was to get that point? Rasing IFR or uping the VE table. If I go with the VE, let me see if I have this correct higher limits reduces fuel, so if I were to multiply the whole table by a giving point, at a time to see were it would fall, ie.102% 103% ect.
Any info would be great, Thanks
Any info would be great, Thanks
#14
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Originally Posted by Bryan Wilkinson
you can change the flow rate of the injectors which will not affect your VE table.