These plots shows the relationship between temperature and resistance for the MAT and Coolant sensors.  These GM sensors use a thermistor as the sensing element.  Typically a thermistor is very non-linear.  That fact is very obvious looking at these plots.  Why GM chose a thermistor with so little sensitivity in the needed temperature range is a bit of a puzzle.  The MAT sensor is a little better off than the Coolant which is good because it is more important.  Air temperature is a key element in determining air density.  The coolant is only used for warm-up enrichment.  The second plot is just expanded a little around the normal operating range.

    These two plots are the same as the above but the output is in ADC counts rather than resistance.  The second is just expanded a little.


    Below is a table of temperature verses (for both the MAT and coolant sensors) resistance, voltage at the ADC, and ADC counts.  In the Edelbrock owner's manual (page 60) there is a table of temperature verses resistance for the coolant sensor.  They didn't give a table for the MAT sensor or indicate its TC so I got these values by putting the sensor into a Thermatron environmental chamber and running it over the below temperature range.  The values I measured are right in the center of Edelbrock's table.  Also I verified that both the MAT and coolant sensors follow the exact same TC curves. 
;
;   Temp      Res     Vadc      ADC
;    -40    93000     4.18      214
;    -20    45000     4.06      208
;      0    24200     3.87      198
;     20    12850     3.57      183
;     40     7130     3.15      161
;     50     5736     2.97      152
;     60     4182     2.69      138
;     70     3207     2.44      125
;     80     2543     2.22      114
;     90     1957     1.98      101
;    100     1577     1.79       92
;    110     1260     1.60       82
;    120     1028     1.45       74
;    130      814     1.29       66
;    140      666     1.18       60
;    150      557     1.08       55
;    160      445     0.98       50
;    170      366     0.90       46
;    180      317     0.85       44
;    185      289     0.83       42
;    189      260     0.80       41
;    193      248     0.78       40
;    200      230     0.76       39
;    203      206     0.74       38
;    220      162     0.69       35
;    248      106     0.63       32
;    284       64     0.58       30