Ford Speed Density Calculator

[murfie]

You can right click and select undo. The calculator will not let you go leaner, than what it was stock, it defaults to around 100% VE. You will need to manually regress coefficients to go leaner. If the vehicle is running leaner than stock, then you probably have mechanical issues. The following is how you watch VE.

Once you are in boost, VE will go linear (blow through) and it needs to stay linear. Especially in the higher RPMs. The SD is basically assuming as much airmass as is physically possible to be going into the cylinder and matching it with fuel mass.

From a 18 F150 2.7l V6 file
Make sure you use inHg, it is the unit calculated from airmass in the ECU, and if you want to do your own regression it needs to be used.
Make sure this is inHg.PNG

Units in inHg.PNG

I removed the 500RPm column because of the negative loads

nothing over 100 out of boost, flat VE in boost.PNG

3d chart of VE

ve 3d.PNG


Now if you wanted to just tell the SD to give it more fuel, forget physics, you need to keep it linear from once it is in boost.
Select the area in boost, and multiply by 1.1 to keep it linear. If I use .9 in this, a bunch of it gets set to 100% VE like a torque curve 4000+.

+10% fuel.PNG

VE after.PNG

VE after adding 10%

+10% fuel after.PNG

VE after removing 10%

Lowering loads.PNG

[metroplex]

Murfie, are you logging stft, ltft or stft+ltft to make the SD adjustments?

[lambda1]

This is a very good explaination of Speed Density, and makes it easy to tune a Speed Density-only car.

Unfortunatelly I get confused whith Coyote which is MAF only

Can someone guide me regarding this part?:

For example, if we're on a MAF Equipped Coyote, and we hit steady state, we may notice the load in our table is off from what we actually have measured via our installed MAP sensor and actual load

I understand the idea, but the question is:
- where the external MAP sensor should be installed in the car to measure the MAP?
- I should install the external MAP to the VCM scanner. I read the pressure values and populate the histogram, but I need to do some math to calculate the actual load from the pressure, so I can compare it with the values in the Speed Density calculator table.

What math should I do to calculate the actual load from the MAP sensor? and then calculate the difference between actual load and the load in Speed Density table?

edit:
... or maybe I should log a histogram with:
y = external map sensor
x = RPM
z = engine load

and just compare it with the speed density calculator table?

[Coldfusion]

[QUOTE=Steven@HPTuners;504979]Available in the latest VCM Suite beta is a new calculator for the Ford Speed Density model. This calculator is quite sophisticated, so an understanding of the process is vital to help get the best results from the calculator. The calculator is capable of giving you the quadratic coefficients including blowthrough, with the goal being to hasten/simplify the process of calibrating this model.

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on a 2015 5.0 Coyote F-150 if I go to mapped point - "Optimum Power" under the speed density calculator and add 20% or "1.2" and select any part of the map and hit the Calculate Coefficients button it will change the engine speed up top to 0.0000010

It also has an effect on Air Charge Multi, Maximum Load, Offset, Quadratic Term, Slope, and Blowthrough slope on .... Engine->Airflow->Speed Density Tab

Make sure you have a backup to compare so you can copy the data back to the way it was. It will corrupt your tune and possibly write bad data to the ECU

Clipboard01.jpg

[Eric@HPTuners]

[QUOTE=Coldfusion;731987]

Available in the latest VCM Suite beta is a new calculator for the Ford Speed Density model. This calculator is quite sophisticated, so an understanding of the process is vital to help get the best results from the calculator. The calculator is capable of giving you the quadratic coefficients including blowthrough, with the goal being to hasten/simplify the process of calibrating this model.

--------------------------------------------------------------------------------------------------------------------------------------------------------------

on a 2015 5.0 Coyote F-150 if I go to mapped point - "Optimum Power" under the speed density calculator and add 20% or "1.2" and select any part of the map and hit the Calculate Coefficients button it will change the engine speed up top to 0.0000010

It also has an effect on Air Charge Multi, Maximum Load, Offset, Quadratic Term, Slope, and Blowthrough slope on .... Engine->Airflow->Speed Density Tab

Make sure you have a backup to compare so you can copy the data back to the way it was. It will corrupt your tune and possibly write bad data to the ECU

Clipboard01.jpg

Can you email me this file?

[Rspec]

[QUOTE=Coldfusion;731987]

Available in the latest VCM Suite beta is a new calculator for the Ford Speed Density model. This calculator is quite sophisticated, so an understanding of the process is vital to help get the best results from the calculator. The calculator is capable of giving you the quadratic coefficients including blowthrough, with the goal being to hasten/simplify the process of calibrating this model.

--------------------------------------------------------------------------------------------------------------------------------------------------------------

on a 2015 5.0 Coyote F-150 if I go to mapped point - "Optimum Power" under the speed density calculator and add 20% or "1.2" and select any part of the map and hit the Calculate Coefficients button it will change the engine speed up top to 0.0000010

It also has an effect on Air Charge Multi, Maximum Load, Offset, Quadratic Term, Slope, and Blowthrough slope on .... Engine->Airflow->Speed Density Tab

Make sure you have a backup to compare so you can copy the data back to the way it was. It will corrupt your tune and possibly write bad data to the ECU

Clipboard01.jpg

Im running into this same issue! Ughhh

[Eric@HPTuners]

Email your tune to eric@hpt*****.c**

[Rspec]

Email your tune to eric@hpt*****.c**

Done!

[spoolin342]

when using the speed density calculator how does one figure out which exh map i would need to make changes for a 2021 GT500 is there a pid or a inferred table i should be looking at

[chuckk]

Any help regarding this ? I understand we can't squeeze more out of the calculator than the "physics" allow but my trims are in the +30%. I don't want to mess up the injector data because I'm running on oem injectors and don't believe I should adjust them.

True speed density application not a MAF based coyote engine.

[21LT1]

How do you lock the map points?