Computech Systems RaceAir Pro - EGT Correctn

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Exhaust Gas Temperature Correction.
Monitoring cylinder exhaust gas temperatures (EGT) can assist in maintaining a consistent and
repeatable tuneup. However, changes in engine inlet air temperature affects the exhaust gas
temperature readings. Use this program to correct an observed exhaust gas temperature reading
to a standard 60 degree Fahrenheit day. Then the Exhaust Gas Temperature Prediction
program can be used to predict an indicated or observed EGT for a different air temperature.
Many things affect EGT (i.e. engine type and design, fuel mixture, ignition timing, engine RPM,
thermocouple location, etc.). Typically, properly tuned methanol fueled engines will have a
corrected EGT between 1050 and 1200 F. The typical gasoline fueled engine EGT will be
between 1250 and 1400 F. These corrected EGT ranges are not necessarily ideal for your
engine. The only way to find the desired EGT for a particular engine combination is by dyno testing
or track testing. See the Tune-Up Information section for information on establishing a baseline
tune up.
Press TUNE-UP then select EGT Correct'n to start this program.
Display Example:
=EGT Correction=
EGT? 1217 (Enter observed EGT  F)
Inlet Temp? 77 (Enter measured air temp  F)
Corr EGT= 1164 (Corrected EGT  F, RECORD this)
Exhaust Gas Temperature Prediction.
Use the Exhaust Gas Temperature Correction program fisrt to obtain a corrected exhaust gas
temperature (EGT). This program will predict what the indicated or observed EGT should be
based on a previously recorded corrected EGT and the current engine inlet air temperature.
Press TUNE-UP then select EGT Predict'n to start this program.
Display Example:
=EGT Correction=
Corr EGT? 1164 (Enter recorded corrected EGT  F)
Inlet Temp? 77 (Enter measured air temp  F)
EGT= 1217 (Target observed EGT  F)
Dial-In, Standard Method.
This program is designed to help class and bracket racers predict an elapsed time (ET) for the
next run based on changes in the horsepower correction factor. The Standard Dial-In method is
Computech's easiest to use and more accurate ET prediction program.
The correction factor method used can be changed from STD to SAE in the program setup area.
The SAE method should produce more consistent results for large barometric pressure changes