Edelbrock Pro-Tuner, User Manual

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many conditions in which they should not be exposed – such as detonation or excessive
temperatures. It is your job as a calibrator to balance all of the factors for your specific
combination and program the best target values into the ECM that you can while keeping
the engine in a safe operating window. There is a desired order in which an engine
control system should be calibrated. A general order of activities is listed below:
1. Verify correct system installation and insure the method of wire and hose
routing will prevent any chance of wear, fraying, or proximity to high
temperatures. Insure software and communication to the ECM is
functioning properly.
2. Perform preliminary calibration activities: load proper sensor and engine
configuration calibrations and limits, set crank trigger offset (& cam offset if
available), scale sensors and map ordinates. It is preferable if the tuner starts with
a known calibration for a similar combination whenever possible; as it greatly
speeds the setup and calibration process.
3. Calibrate under steady state conditions for every engine speed and throttle
position (load) - while optimizing fuel, ignition timing, and airflow – and
completing the various maps at each point.
4. Optimize starting, warm-up, and idle calibrations for various temperatures and
conditions. (Cold starts, hot restart, etc.)
5. Calibrate transient fueling (acceleration and deceleration) parameters if needed to
optimize fuel during non-steady state conditions.
Fundamental Steady-State Engine Calibration Goals
1. Minimize BSFC at part-throttle operating conditions.
2. Maximize Torque at WOT.
3. Stay within emissions constraints.
5. Stay within EGT limits
6. Minimize drastic or erratic map value changes between cells
The important thing to remember is to balance all of the factors to create the best
compromise between them.
For example: as a calibrator, you may be personally focused on running quality. You may
find that running quality continues to improve as you advance the spark at a particular
operating point. Even though running quality may actually improve as spark is advanced
into the knock region – one should not cross those limits in pursuit of optimizing one
variable, because doing so could cause engine damage.
The best calibration attempts to keep each variable in the middle of the window for every
operating point. While this may not always be possible due to operating conditions or
engine hardware and design; every effort should be made to keep away from the edges
of the window. For example, let’s say you calibrated your engine on the lean side of the
wide open throttle air/fuel window to reduce fuel consumption during the race. While it
may be OK for that specific combination at that time, you would have to ask yourself,
1.Is the calibration robust enough if my crew chief advances the cam 2 degrees?
2.Will the engine be OK if fuel quality varies?
3.Will the engine detonate if lugged in gear?
For these reasons and others, it is desirable to stay in the center of the variable’s window