I did some searching and couldn't find a transfer function for a 90-93 AFM. Does anyone have it available?

Volts versus Airflow (g/s).

 

Well, I nicked an AFM transfer function from the AEM miata calibration.

g/s Volts
99.609375 0
99.609375 0.16
99.609375 0.31
91.796875 0.47
78.515625 0.62
62.5 0.78
30.078125 0.94
22.265625 1.09
18.75 1.25
17.1875 1.4
15.234375 1.56
13.28125 1.72
11.71875 1.87
10.546875 2.03
9.765625 2.18
8.59375 2.34
7.421875 2.5
5.078125 2.65
3.125 2.81
0 2.96

I plugged this in to my standalone controller (PROEFI-ish), and it sucks. The airmeter reads about double the airflow of the speed density calculation at idle. It gets even further off at high flow.

Can anyone verify if the above transfer function should be correct?

 

I suspect this is probably what you're looking for: http://miatajoe.50megs.com/