10
correction factor of 1.05 (adding 5%). This is done by selecting this menu
option and entering this factor. There is no decimal shown, so you will be
entering this value as a three digit number. For example, 1.05 will be entered
as 105, 0.95 will be entered as 095 (subtracting 5%). Likewise, if fuel
mileage reading is known to be off by 5%, say the gauge is reading 5% low,
enter a correction the same way (105). As with the shift light entry field, you
will use the left button to change the digit above the cursor. Hitting the right
button will move the cursor to the next digit. After the last digit is entered
you will return to the main menu. The factory default value is 100,
representing 1.00, or no correction factor. Also, if the MAF sensor has been
recalibrated or replaced with one sized differently, this correction factor,
which is based on the new sensor’s scalar, can be u
sed to compensate for this
change. For Example, and SCT BA2400 MAF sensor has a scalar of 0.47.
To correct for this you’ll need to enter 213 (representing 2.13) which is the
same as dividing the MAF reading by 0.47. An SCT BA2800 has a scalar of
0.40, so 250 would be entered in this situation (same as dividing MAF by
0.40).
t) Altitude
. Enter your altitude (elevation) in feet as a 4 digit number. For
example, 700’ above sea level would be entered as 0700, 2500’ would be
entered as 2500. This entry is used in some of the calculations to improve
their accuracy.
Not all gauges will have this option, some vehicles have a
barometric pressure sensor that automatically performs this function.
u) Average Fuel Economy.
Selecting this will display the average calculated
fuel economy since the last reset. Average in only calculated when
instantaneous fuel economy is displayed on the gauge.
v) Fuel Economy Reset.
Resets the running average of fuel economy and starts
the calculation over again.
w) Analog 1
. This selection allows the user to enter a conversion for this 0-5v
input, which uses the right pin of the three pin connector. To read raw volts,
enter “001.0” for slope, and “000.0” for intercept. This is the default setting
as well. For example, say you want to input the analog output of a wide band
O2 sensor kit. You know from the kit’s documentation that the output is
scaled such that 0v=10 A/F ratio, and 5v = 20 A/F ratio. The conversion
would then be a slope of 002.0, with an intercept of 010.0. In other words,
voltage multiplied by 2 plus 10 would equal A/F ratio. In this example, a
voltage of 5 would result in 5*2+10 equals 20 A/F ratio. Another common
use for these analog inputs are for MAP sensors. The GM 3 bar MAP is a
common sensor used to measure high levels of boost. The conversion for this
sensor would be V*9.2-14.7, or a slope of 009.2, intercept of
-
14.7. The
intercept can be tweaked if the sensor does not read “0” with the key on,
engine off. Our personal 3 bar MAP had a slight zero offset that we adjusted
by changing the intercept value. These inputs use a 10 bit A/D device, and are
highly accurate to .01 volts. You will only see a resolution of 0.1 volt
displayed, but the calculations are based on the full 10 bit conversion and are
not rounded off for higher accuracy
. Note that the negative symbol, if
required, needs to be in the far left digit.
For example,
–
9.7 should be
entered as “
-
09.7”. Aeroforce sells a line of OEM sensors that are compatible