Edelbrock 3550 - Manual (Page 30)

30
Pro-Flo EFI Installation Instructions
©2005 Edelbrock Corporation
Brochure No. 63-0115 Rev. 10/05
Electronic Engine Management
The Edelbrock Pro-Flo system uses the Speed-Density method of electronic engine management, in which fuel and spark requirements are
based on engine speed (RPM) and engine load (manifold pressure and temperature).
The Electronic Control Unit (ECU) receives signals regarding engine speed (from the distributor), and the three load factors consisting of coolant
temperature (ECT), Manifold Absolute Pressure (MAP) and air temperature (MAT). Once the ECU has determined the engine operating point (RPM
and Load factor), it uses tables programmed into it to instantly calculate correct spark advance and injector pulse width.
A more detailed description of electronic engine management can be found in the Owner’s Manual for your Pro-Flo system. One possible point of
confusion does need to be clarified. The Pro-Flo system displays vacuum rather than the less-familiar manifold pressure. This vacuum reading is
based on the following SAE standard atmosphere:
Barometer 29.5 in Hg
Temperature 77°F
Because of this, the vacuum figures displayed on the Calibration Module may differ from the vacuum indicated by a true vacuum gauge,
particularly at extreme high or low altitude.
The Pro-Flo tables come pre-set from factory for the engine
combination that you specified when you ordered your computer
chip. This factory calibration must be altered with the Calibration
Module to optimize performance. The Calibration Module allows
you to modify the fuel and spark tables at various engine speeds
and levels of vacuum. These tables may be used for recording
your modifications to the base table with your own fuel pulse
width and spark advance figures. For information on using the
Calibration Module to enter your figures into the Pro-Flo ECU refer
to the CALIBRATION MODULE section in the Owner’s Manual.
FUEL MODIFIER TABLE
SPARK MODIFIER TABLE