Cyl air mass change
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Cyl air mass change Looking for help on 6.0 trk 06. Has heads long tubes cam . Engine ran out of
injector (stock) .Replaced With Delphi 44 shorty ,after rescaling for injector
writing new ve grams per cyl went up. Scaled injector lower value changed
ve .Now g/cyl flatten out at .80 .Is this air mass actual measured flow or a
calculation of fueling ?
injector (stock) .Replaced With Delphi 44 shorty ,after rescaling for injector
writing new ve grams per cyl went up. Scaled injector lower value changed
ve .Now g/cyl flatten out at .80 .Is this air mass actual measured flow or a
calculation of fueling ?
Originally Posted by shortturn
Looking for help on 6.0 trk 06. Has heads long tubes cam . Engine ran out of
injector (stock) .Replaced With Delphi 44 shorty ,after rescaling for injector
writing new ve grams per cyl went up. Scaled injector lower value changed
ve .Now g/cyl flatten out at .80 .Is this air mass actual measured flow or a
calculation of fueling ?
injector (stock) .Replaced With Delphi 44 shorty ,after rescaling for injector
writing new ve grams per cyl went up. Scaled injector lower value changed
ve .Now g/cyl flatten out at .80 .Is this air mass actual measured flow or a
calculation of fueling ?
Originally Posted by shortturn
Looking for help on 6.0 trk 06. Has heads long tubes cam . Engine ran out of
injector (stock) .Replaced With Delphi 44 shorty ,after rescaling for injector
writing new ve grams per cyl went up. Scaled injector lower value changed
ve .Now g/cyl flatten out at .80 .Is this air mass actual measured flow or a
calculation of fueling ?
injector (stock) .Replaced With Delphi 44 shorty ,after rescaling for injector
writing new ve grams per cyl went up. Scaled injector lower value changed
ve .Now g/cyl flatten out at .80 .Is this air mass actual measured flow or a
calculation of fueling ?
Originally Posted by shortturn
I do have it in sd maf failed at 0 but still pluged in will this still calc air
VE is stored in GM Specific units.
GMVE = grams of air * temp in Kelvin / kPa
thus
g = VE*MAP/charge temperature
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EFI Live's scanner pulls grams/cylinder using the PCM's RAM. When the MAF is active, we log GM.CYLAIR_DMA to grab air mass. The airflow value is either provided by the MAF or a blend of the MAF and VE calculated airflow.
When the MAF is off (SD), we log GM.DYNCYLAIR_DMA. GM.DYNAIR provides a calculated airflow value based on the VE table and several other sensors (same as the blended part above - only minus the MAF).
DMA pids: These are the instantaneous values the PCM is using to make it's fuel/spark calculations. The "DMA" on the end of our pids means Direct Memory Access.
When the MAF is off (SD), we log GM.DYNCYLAIR_DMA. GM.DYNAIR provides a calculated airflow value based on the VE table and several other sensors (same as the blended part above - only minus the MAF).
DMA pids: These are the instantaneous values the PCM is using to make it's fuel/spark calculations. The "DMA" on the end of our pids means Direct Memory Access.
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From: Texas where Bigger is Better
Originally Posted by SSpdDmon
EFI Live's scanner pulls grams/cylinder using the PCM's RAM. When the MAF is active, we log GM.CYLAIR_DMA to grab air mass. The airflow value is either provided by the MAF or a blend of the MAF and VE calculated airflow.
When the MAF is off (SD), we log GM.DYNCYLAIR_DMA. GM.DYNAIR provides a calculated airflow value based on the VE table and several other sensors (same as the blended part above - only minus the MAF).
DMA pids: These are the instantaneous values the PCM is using to make it's fuel/spark calculations. The "DMA" on the end of our pids means Direct Memory Access.
When the MAF is off (SD), we log GM.DYNCYLAIR_DMA. GM.DYNAIR provides a calculated airflow value based on the VE table and several other sensors (same as the blended part above - only minus the MAF).
DMA pids: These are the instantaneous values the PCM is using to make it's fuel/spark calculations. The "DMA" on the end of our pids means Direct Memory Access.
remember the values you get through DMA PIDs (EFI nomenclature)/MPIDS (HPT name) are just lookup. it's not what's real. if you set your VE table to something really low, your DYNCYLAIR is going to be low, no matter how much air you really got going through there. if your tune been raped and pillaged by an IFR tweaker, most of the time your VE tables will be left completely stock, so your newly modded ride will show the exactly same airflow as before. this is of course wrong, but this is how it usually is.
the only way to arrive at more realistic VE (which effectively will change DYNCYLAIR) is to start with as good of an estimation of IFR as you can get (it will never be perfect as neither injectors nor the fuel pressure are linear) and then adjust VE until the AFR on the wideband follows your commanded AFR.
AFR=airmass/fuelmass and
fuelmass=IPW*IFR
if you don't adjust airmass, you can get AFR to still 'agree' by tweaking fuel mass. also, if you're changing both airmass and fuelmass at the same time, there's an infinite number of solutions to this problem. thus set your IFR to what's most realistic, point that AFR where it should be, and let the VE describe the real new airflow.
the only way to arrive at more realistic VE (which effectively will change DYNCYLAIR) is to start with as good of an estimation of IFR as you can get (it will never be perfect as neither injectors nor the fuel pressure are linear) and then adjust VE until the AFR on the wideband follows your commanded AFR.
AFR=airmass/fuelmass and
fuelmass=IPW*IFR
if you don't adjust airmass, you can get AFR to still 'agree' by tweaking fuel mass. also, if you're changing both airmass and fuelmass at the same time, there's an infinite number of solutions to this problem. thus set your IFR to what's most realistic, point that AFR where it should be, and let the VE describe the real new airflow.
Originally Posted by shortturn
redhardsupra
Do you know correct injector scaling for Gm 8.1 non marine injectors ?
Do you know correct injector scaling for Gm 8.1 non marine injectors ?
30#/hr
To be accurate at all load levels though, you'll also want to copy the other related tables as well (injector pulse width voltage adjustment, minimum injector pulse width, default minimum injector pulse width, small pulse adjust)
