so, im looking at bringing an old idea that i used in a previous project over that pertains to MAP sensor scaling on the tables as the way i have seen others adding support for other MAP sensors is rather clunky and a bit overkill. To start this idea comes from what i used when i worked on converting motronic to speed density. basically all MAP sensors read 0-5V regardless of if its 2BAR, 3BAR and so on right? their factors and offsets just change to linearize the sensor as for how much positive pressure it can read. now with that known you can essentially used one axis for all sensors but run the base value from the ADC through a factor and offset to adjust the output viewed in your maps.
i will be using the axis for the stock VE table for my example here. so i took my previously made equations for MAP sensor factor and MAP sensor offset and added these to my tunerpro definition. the equations are below.
MAP sensor factor
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IF(X==0;0; IF(X==1;50; IF(X==2;158.88235; IF(X==3;210.89308; IF(X==4;82.61049;01)))))/51
MAP sensor offset
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IF(X==0;0; IF(X==1;10; IF(X==2;-02.35764; IF(X==3;0.222013; IF(X==4;6.9558;01)))))
than i have a constant value that is in some open code space in the that can needs to be set as per the list below.
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1=Stock GM Sensor
2=3BAR MAP Sensor
3=4BAR MAP Sensor
so after this i created a sort of fake axis in some open code space in the calibration with my constant set to 1 for the factory sensor than worked with tweaking the values of my axis. this is what i ended up with to make my constant of 1 for the stock MAP sensor line up with what was the original axis.
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9F
now i make another axis like the first one that reads the raw HEX but this time i plug in these equations for each row of the axis.
rows 0-17
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CELL(ROW()+1;COL();FALSE) - (THIS()*THAT(7210;0;0;FALSE)/1.04296875)
row 18
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(256-THIS())*THAT(7210;0;0;FALSE) + THAT(8577;0;0;FALSE)
after doing all of this i got an axis that was 1-1 perfect with the original KPA axis. seems pointless so far right? trust me, its not. now i had to go into my VE table and tell the XDF to used linked scale for the MAP axis than pick my semi fake KPA axis i made for what to read for the pressure axis. after thats done i can go into the MAP sensor constant and pick whatever MAP sensor im using via 1, 2 or 3 and from than on the VE table MAP axis will automatically be scaled and display the proper axis for that sensor.
bonus!!!
if you make a third table that reads the KPA axis you can convert this to manifold pressure relative to atomspheric pressure as well!
in row equations you need to use this equation.
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(THAT(7884;0;0;FALSE))*0.14503773800722-14.6959494
now its as easy as just changing 1 constant and your VE table or whatever you want to apply this to can be automatically scaled for whatever MAP sensor you are using. and you will notice in my pictures that the raw HEX code on my base axis never changed because 0-5V is always 0-5V from a MAP sensor. i will make an XDF and a pre-patched P59 BIN with all of this so everyone can look at it more in depth later.
Stock Sensor
- Screenshot 2024-08-22 170930.jpg (150.69 KiB) Viewed 4608 times
3BAR sensor
- Screenshot 2024-08-22 171133.jpg (149.44 KiB) Viewed 4608 times
4BAR sensor
- Screenshot 2024-08-22 171303.jpg (150.3 KiB) Viewed 4608 times
