Precision Turbo and Engine BigStuff3 GEN3 PRO SEFI System Hardware & BigComm Software - Manual (Page 86)

BigStuff3 Pro SEFI System
Version 2.1 – February 2011 79
45. Warm Up
Before the engine reaches normal operating temperature, i.e. 180
o
additional fuel is required as a
function of engine coolant temperature and manifold absolute pressure (for speed-density
applications). To calibrate “warm up enrichment” fuel go to the Main Tool bar and highlight “Warm
Up.” Keep the left mouse button depressed and slide the cursor down to select Coolant Correction or
Air Temperature Correction, depending on the table to be accessed.
46. Air Temperature Correction
The inputs from this table are used by the ECU if “Alpha N” was the control algorithm selected during
the Main Configuration set up.
If “Speed Density” the control algorithm was selected, the ECU
ignores inputs from this table.
For Alpha N systems, the ECU uses input from this table for air temperature compensation. The fixed
numbers in the input table represent air temperature from –14.8
o
to 244
o
F. The ECU uses the user-
defined inputs for each temperature point to add or subtract fuel relative to the base fuel map values.
While the engine is running, a “real-time Ellipse” will move within the Air Temperature table
relative to the current engine Coolant Temperature “operating point”. Use it as a point of reference to
help calibrate the Air Temperature table.
To change a value in the Air Temperature table, move the cursor using the PC’s mouse or arrow keys
to the cell to be changed. Input the desired value and hit
“Enter”
to save the change. The input
values need to be smaller working from the left to right. As the engine warms up it needs less Air
Temperature correction (added fuel).
The inputs shown in the table below can be used as a baseline.