Holley COMMANDER 950 - Manual (Page 60)

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AE of MAP vs. Coolant Temperature (%) – Colder engine temperatures may require different transitional fueling
requirements. This table allows the user to tailor the synchronous fueling to the engine temperature. Numbers are percentage
based with number below 100 subtracting a percentage from the base Delta MAP and numbers higher adding a percentage to
the base Delta MAP.
Modifiers – The following three tables adjust the base fuel delivery according to various external sensors. All table entries are
in percent where numbers greater than 100 increase the fuel delivered and values lower than 100 decrease the amount of fuel
delivered.
Figure 43
Air Temperature Enrichment (%) – This table adjusts the base fuel delivery based on the air temperature. The density of air
increases one percent for every eleven degrees Fahrenheit of temperature increase. Once the engine is tuned correctly at a
certain temperature, the fuel should be adjusted accordingly for all temperatures warmer and colder than the tuning air
temperature.
Coolant Temperature Enrichment (%)– This table is similar to a carburetor’s choke function. At cold engine temperatures,
the engine will need more fuel because some of the injected fuel will stick to the manifold walls or to the walls of the cylinder.
At higher engine temperatures, this table can be used to increase the amount of fuel delivered to help cool the engine down.
Barometric Compensation (%) – This table only appears in Alpha-N mode and allows the user to adjust fuel delivery as
altitude changes.
SPARK – These are all the parameters for adjusting the spark delivery to the engine.
Main Spark Map– This is the primary spark map used by the ECU to determine where to make the spark. The table is
organized just like the fuel map where moving further to the right represents an increase in the engine speed and traveling up
the table represents an increase in the engine load. The number in each cell represents the actual timing degrees for the
engine. If the ECU is attached to the PC, the cell background color will change to indicate which cell is being utilized by the
ECU for its spark calculations. This cell background color change will move around as the engine speed and load change, just
as in the fuel map. The spark map also has most of the data monitor features of the fuel map. The spark map has the same
feature as the fuel map, whereby large changes can be made by selecting an area of cells and performing a mathematical
function to them (+,-,/,*,=).
Main Spark Graph – This is a graphical representation of the main spark map. You will want to view some of the supplied
spark maps to see what a spark graph should look like once finished. You can move around this map using the arrow keys
and can alter values by pressing the shift or ctrl key along with the up or down arrow. Naturally, the up arrow increments the
values and the down key decrements the values. The shift key causes the step amount to be one degree whereas using the
ctrl key causes the changes to be made by five degrees.