mowton
December 24th, 2015, 02:16 AM
I have posted this in several forums to maximize my responses...sorry if redundant.
Lately I have been trying to figure out GM's intent of the long term trim cell strategy for the early E38's (pre 2008). If you look at the MAP and RPM Boundaries (don't believe they are available in EFIL, at least I have not found them yet), the RPM is 8192 for all 3 and the map is 71, 115,115 kPa which in my understanding leaves 2 LTFT possibilities (0 and 4)???????. 4 if you count EVAP Open/Closed. 2008+ they went to airflow model boundaries but in these cases, there appears to be only 2 cells as well (31 and 64).
In boosted setups and using my preferred PE enable strategy of 85 kPa (low pedal % to trigger on load), it doesn't leave FTC 4 much room to adjust properly and I find it "contaminating" my PE fueling with positive trim adjustments. Couldn't find much info googling so I have a 2007 Vette which I have set the Boundaries similar to the way I do a GEN III setup...RPM -- low 100 above idle rpm, high at 4000 and med the mid point between the two. For the MAP I use 5 above the idle kPa, high at 85 (PE trigger) and med again half way between.
Will see if it gives more granularity and preclude invalid trim data from being developed and contaminating the PE fueling if positive.
Merry Christmas and Happy New Year to all our clients, EFI Live Forum friends and especiall the EFI Live crew for supporting us throughout the year.
Ed M
Lately I have been trying to figure out GM's intent of the long term trim cell strategy for the early E38's (pre 2008). If you look at the MAP and RPM Boundaries (don't believe they are available in EFIL, at least I have not found them yet), the RPM is 8192 for all 3 and the map is 71, 115,115 kPa which in my understanding leaves 2 LTFT possibilities (0 and 4)???????. 4 if you count EVAP Open/Closed. 2008+ they went to airflow model boundaries but in these cases, there appears to be only 2 cells as well (31 and 64).
In boosted setups and using my preferred PE enable strategy of 85 kPa (low pedal % to trigger on load), it doesn't leave FTC 4 much room to adjust properly and I find it "contaminating" my PE fueling with positive trim adjustments. Couldn't find much info googling so I have a 2007 Vette which I have set the Boundaries similar to the way I do a GEN III setup...RPM -- low 100 above idle rpm, high at 4000 and med the mid point between the two. For the MAP I use 5 above the idle kPa, high at 85 (PE trigger) and med again half way between.
Will see if it gives more granularity and preclude invalid trim data from being developed and contaminating the PE fueling if positive.
Merry Christmas and Happy New Year to all our clients, EFI Live Forum friends and especiall the EFI Live crew for supporting us throughout the year.
Ed M