Individual Cylinder Fuel Trim Multipliers...
08-27-2012, 09:54 PM
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Individual Cylinder Fuel Trim Multipliers... I know you all have probably seen my problem with Split BLM's...I am baffled.
I was playing with my Individual Cylinder Fuel Trim Multipliers...I have made some changes and gotten the BLM's closer, but not close enough. I have gotten to a point where I am unsure how much more I can safely change these numbers, and how do I know if I have gone too far, or if I need to change them more?
I know about the method of using an IR Thermometer to measure the Header Tubes about 2 inches down from the Head and using the middle 2 as a judge....but how do I know if the middle ones are even the right temps? What is a good temp??
I was playing with my Individual Cylinder Fuel Trim Multipliers...I have made some changes and gotten the BLM's closer, but not close enough. I have gotten to a point where I am unsure how much more I can safely change these numbers, and how do I know if I have gone too far, or if I need to change them more?
I know about the method of using an IR Thermometer to measure the Header Tubes about 2 inches down from the Head and using the middle 2 as a judge....but how do I know if the middle ones are even the right temps? What is a good temp??
08-28-2012, 02:26 AM
#2
The best way is to have 1 wideband in each cylinder
Of course that's not possible for que average Joe, so the only way is to read plugs.
EGTs are an indication of AFR, but you don't know if 1 cyl is misfiring or which one is rich or lean.
There's no base to know how many degrees equal to stoich.
Set the PCM to open loop and command like 14:1 AFR, meassure EGT and make them all the same. The hottest one is the leanest, so enrich that cylinder and try again
Plugs don't lie, I prefer to read them
Of course that's not possible for que average Joe, so the only way is to read plugs.
EGTs are an indication of AFR, but you don't know if 1 cyl is misfiring or which one is rich or lean.
There's no base to know how many degrees equal to stoich.
Set the PCM to open loop and command like 14:1 AFR, meassure EGT and make them all the same. The hottest one is the leanest, so enrich that cylinder and try again
Plugs don't lie, I prefer to read them
08-28-2012, 03:12 AM
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I have 2 O2 bungs for widebands and I will be riding with a wideband on each bank soon...I have a new one coming in and I think I am going to try and tune one side at a time...just switch it back and forth to measure each bank...tune, flash, and then retest each bank. Slow and tedious, but I think that will suffice for now.
I am just scared of changing this table TOO MUCH on one side or even one cylinder. I dont want to mess up my motor and I am mainly curious how much people have been changing these numbers when they tune, and what to...just for an idea.
I am just scared of changing this table TOO MUCH on one side or even one cylinder. I dont want to mess up my motor and I am mainly curious how much people have been changing these numbers when they tune, and what to...just for an idea.
