Is there a way to develop a 'rough' VE table through a properly calibrated MAF curve in a GEN III pcm?
i'd imagine i could use fuel mass/air mass and some algebra to find VE..
Has anyone attempted this?
Is there a way to develop a 'rough' VE table through a properly calibrated MAF curve in a GEN III pcm?
i'd imagine i could use fuel mass/air mass and some algebra to find VE..
Has anyone attempted this?
make a custom histogram, with MAP/RPM axis, and then for data use all the other data to calculate the VE.
I guess the logic is following: compare MAF-based airflow to theoretical cylinder filling.
For MAF isn't it so that you divide MAF grams/second value with rpm (and rpm needs to be divided with 60 to get revs/second). And this again is divided by the number of cylinders. So the end-result is measured airmass per cylinder at certain conditions. Wich then needs to be compared to the theoretical value per each MAP/rpm cell.
In other words, you need to define a custom PID with something like this: ([SENS.40.MET]/([SENS.70]/60))/8
...where SENS.40.MET is MAF value as grams/second and SENS.70 is revs per minute, which is divided by 60 to ger revs per second. And 8 is obviously a number of cylinders.
Am I right or wrong?
Does anyone have Banish' book where the VE formula is presented? I have both books, but cannot find now either of them...
Last edited by Pekka_Perkeles; 05-07-2014 at 06:34 AM.
VE = MAF / (Displacement x P stp x Speed)
Last edited by jim2092; 05-07-2014 at 11:39 AM.
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We do not have MAT as a PID in HPTuners for Gen3 stuff. At least I've not seen it as of yet. I do know the other software has this PID to log though. You would need the reported MAT to properly calculate VE. Without that your VE will be scewed using IAT only.
On the Gen3 stuff it's much easier to go the opposite way. Dial in VE first and then generate a MAF table by overlaying dynamic airflow (while running in SD) on the MAF Freq table.
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actually theres IAT and MAT in gm vocabulary.
Either way, LSxpwrdZ, i understand the VE would be a bit skewed due to just using IAT, but don't you think it would be better than having to start off at zero? if the IAT gives a sample error of +10% then I would more or less have to decrease the entire ve by 10 percent.
Seems like the GMVE stuff is more appropriate for the e38's huh? since you can log mat and all.