VE Tables using MAF

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L31MaxExpress

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Something I have done to make VE tables less of a pain. I now tune the MAF transfer table using MAF only. Then when I am happy with the MAF calibration, I datalog and get a as much of a base VE table for a starting point.

My Calculated VE, MAF fuel trims and VE fuel trims are all filtered to prevent data points from saving during MAP and TPS movements that activate transient fueling. I will get a screenshot of the filters when I have my tuning laptop fired up. I forgot to take a picture of them. Going off memory, my MAP has to change less then 1 kpa in 100 msec and TPS has to change less then 1% in 100 msec for the data to save in the histograms.

Dynamic air calibration from MAF
Dynamic Air Calculated =
(MAF gms/sec X 120) / (#Cylinders X RPM)

VE Calculation from MAF
VE=(DynamicAir X IAT in Kelvin X 0.28705) / (Cylinder Volume X MAP in Bar)

Now put both parts together.
VE=((MAF gms/sec X 120) / (#Cylinders X RPM)X IAT in Kelvin X 0.28705) / (Cylinder Volume X MAP in Bar))

VE Equation
[16.71] is HPTs way of inserting MAF in gms/sec
[12.56] is RPM
[15.240] is IAT in Kelvin
[11.99] is MAP in Bar
120 & 0.28705 are fixed values
8 is Number of Cylinders
0.7875 is volume of 1 cylinder in Liters


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Reluctanse

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Another good thread from you here.
Question... i keep going in circles with what I'm reading here, would you recommend dialing in the MAF frequencies and then VE tables, or vice versa?
 

RDF1

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All i do is get engine up to temp. Disable MAF, Tune VE table.
Then enable MAF only. Tune maf and then go back to CL and confirm everything plays happy together.

EFI Live has a Calc.VET thread about tuning both VE and MAF at the same time. just havent tried it yet.
 

L31MaxExpress

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All i do is get engine up to temp. Disable MAF, Tune VE table.
Then enable MAF only. Tune maf and then go back to CL and confirm everything plays happy together.

EFI Live has a Calc.VET thread about tuning both VE and MAF at the same time. just havent tried it yet.
I do mine the opposite. MAF first, then VE. Then again I am not a speed density fan and a MAF generally offers a better starting point so that I can tune other aspects first. Startup, Idle, Timing, etc.

Now that I have been tuning this way, it is even easier.

I do most of my actual editing and flashing in open source.
 
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