Calibrating MAF in ATR

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'08 CPW Mazdaspeed 3
I must be dumb, because I can't figure out what I am supposed to do to properly calibrate the MAF in ATR.

I did the log as described in the manual...1500 RPM in second, slowly accelerate until MAF exceeds 100 g/sec. Then shift into neutral and go WOT until it exceeds 30 g/sec.

I have the log, but now I don't know what to do with it. I have LTFT and STFT numbers, as well as MAF volts, MAF (g/sec), RPM, etc. I made the chart just like it is shown in the manual.

So what is the next step? I opened up ATR, loaded my map, and looked at the Sensor Cal. Tables section. Guessing MAF table A is for the partial throttle and MAF table B is for WOT? I can't find that anywhere in the help manual, but that's what I guessed. Am I supposed to just use the scale function to make the numbers equal for all the logged MAF voltage points, or only where LTFT and STFT numbers are a bit high/low?

Basically, I can't figure out the next step after getting the log together. I've read through the manual a number of times now, and can't seem to figure it out. I'm sure it's obvious, but the answer is just eluding me right now.

Thank you for any help!
 
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I feel like a idiot too because I could not figure it out either so I had someone else do it for me. The instructions dont seem to be all that clear or Im just stupid,Im leaning towards me being stupid..
 
Good to know I'm not alone. All I ever heard was "it's super easy"...I read the instructions and it's like they left a section out. I'm just hoping someone who has actually gone through the process will speak up and explain what to do, because I'd like to start working on the tune a bit more, but don't want to start until the MAF is calibrated correctly.
 
Well nobody seems to be helping you here so it must not be all that easy or you would think someone would speak up. I bet its one of those things that when you do figure it out its super easy after that.
 
ok it is super easy and you all are idiots, but anyways!!

Once you find out your different fueltrims
0-5g/s = x.xx
5.01-16g/s= x.xx
16.01-28g/s- x.xx
28.01-77g/s= x.xx
77-max= x.xx

so what you do with these numbers that were recorded is you goto MAF A and B (pick on to start then copy and paste in the other) then you will multiply the percent change, so if 0-5g/s you were +5.7% off you would highlight the bottom row (air flow in g/s) form 0 to 5 g/s then hit e and type in 1.057. This tells the program to add 5.7% more airflow given that range. Visa versa if it was -5.7% you would hit e and the type 0.943, which will take away 5.7% airflow. Then make sure to apply this to all of the MAF ranges and smooth out the points between the breaks. Do this by highlighting 2or 3 cells on each side of the break and hit h. This will cause a smooth line from the end points.

HOpe ATR for dummies helps.
 
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