Ford Speed Density tuning on EcoBoost...

[GapRider]

ever seen a GM VE table? looks like new mexico.

So it's a common thing to see? Attributed to harmonics I guess where certain RPM's have inherently higher mass/MAP?
So you think these mass and load graphs look right?
OP mass and load graphs.JPG

[Higgs Boson]

2016 Z06 stock VE table

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[Higgs Boson]

2014 Jeep Wrangler

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[GapRider]

2014 Jeep Wrangler

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OK, I guess it's common then, thanks. I still wonder what the reason for those peaks/ridges is, do you think it has to do with harmonics?

[Higgs Boson]

it has to do with zone boundaries and how they have spaced them. i don't know if you can edit them in the Fords but you can edit and smooth, etc the GM stuff and make it look normal, but I am not sure that's the right way to do it.

[GapRider]

[QUOTE=Higgs Boson;463444]it has to do with zone boundaries and how they have spaced them. i don't know if you can edit them in the Fords but you can edit and smooth, etc the GM stuff and make it look normal, but I am not sure that's the right way to do it.[/QUOTE

Is that like laminar flow boundaries, I haven't heard about zone boundaries?

[Trent_Petersen]

it has to do with zone boundaries and how they have spaced them. i don't know if you can edit them in the Fords but you can edit and smooth, etc the GM stuff and make it look normal, but I am not sure that's the right way to do it.

Is that like laminar flow boundaries, I haven't heard about zone boundaries?

From the little I know, Ford does not use zones like GM does for its VE calculations.

GapRider if you are curious (even through it doesn't apply to our Fords) you should have a few newer GM calibrations in your samples folder you can open up and look at. The file "2014 Chevy Corvette E92" is a good example. Open that file, Edit -> Virtual Volumetric Efficiency. There is a checkbox in the VVE editor to show zone boundaries.

[GapRider]

From the little I know, Ford does not use zones like GM does for its VE calculations.

GapRider if you are curious (even through it doesn't apply to our Fords) you should have a few newer GM calibrations in your samples folder you can open up and look at. The file "2014 Chevy Corvette E92" is a good example. Open that file, Edit -> Virtual Volumetric Efficiency. There is a checkbox in the VVE editor to show zone boundaries.

OK I'll check that out, thanks!

[06300CSRT8]

Bumping this old thread back from the dead....

Did anyone finish off building a virtual VE table based on the inputs we have in our tunes? One thing that stumped me, even after getting through setting up a virtual VE table, is what of the 4 parameters needs to be changed to arrive at a more accurate VE table? How would you know if the error observed via fuel trims adjusting as a slope issue, offset issue, or both? Changing either will fix that one point, but if you get it wrong will effect a lot of other points inadvertently.

[tbrtuning]

I created something that I've used successfully but I never really commented it and cleaned it up for other people to use. I posted it a while back but never got any feedback on it...

If you can figure out how to use this it demonstrates the relationship between slope and offset. You can get it close by just guessing and moving in the correct direction without using the spreadsheet once you see the relationship between slope and offset.

Ford Speed Density Calculated Good For Ecoboost.xlsx

[murfie]

https://www.easycalculation.com/stat...regression.php

enter your airmass values as x and your Map values in inHg as y. it will generate the best fitting offset, slope, and quadratic values to use.

https://www.hptuners.com/forum/showt...-5k-rpm/page11

I posted some maths in this thread if you need to figure out your airmass.

I export the file to a .csv then use excel to filter out different MP weight and RPM. from there I copy map values and air mass values in you get the quad, slope, and offset for the mapped point and RPM.
Make sure to use your inferred MAP and MAF with the corresponding inferred air mass. Its good to have either a lot of different MAP values in one RPM or as the example below data across a wide RPM range. with the wide RPM range you would end up using the same values just like you can see in the stock tune some times.
MAP.PNG
LBm.PNG
Quadratic.PNG
SD OP.PNG

[Witt]

There's also a factor that's able to be logged in other software for VE correction for standard temperature as well as total VE correction. Even with just correction for standard temp, you can probably calculate the total aircharge correction due to outside variables as shown in equations 6 and 7 in this patent... https://www.google.com/patents/US6851304

[VodeAn]

From the little I know, Ford does not use zones like GM does for its VE calculations.

GapRider if you are curious (even through it doesn't apply to our Fords) you should have a few newer GM calibrations in your samples folder you can open up and look at. The file "2014 Chevy Corvette E92" is a good example. Open that file, Edit -> Virtual Volumetric Efficiency. There is a checkbox in the VVE editor to show zone boundaries.

Ford's internal tool for making the VE tables may have zones which would explain the similarities to the GM table, all the "peaks"

[VodeAn]

So it's a common thing to see? Attributed to harmonics I guess where certain RPM's have inherently higher mass/MAP?
So you think these mass and load graphs look right?
OP mass and load graphs.JPG

I don't believe harmonics has anything to do with it. Then again I did sleep though some NVH lectures in my engineering classes...

Edit: Harmonics, or specifically the reverberation of air in a manifold system and the effect of air in a system on itself is certainly a consideration when trying to understand the system. I just don't see a correlation between it and the "steps" in the data in the VE table. I would attribute the observed pattern to the method by which the data is derived to populate the table or to an unknown variable. It is possible that OEMs are taking the airmass prediction calculations into account when populating the VE table in ways we have yet to fully comprehend.

[21LT1]

jerk not snap