Precision Turbo and Engine BigStuff3 GEN3 PRO SEFI (LS1) System Hardware & BigComm Software - Manual (Page 66)

BigStuff3 Pro SEFI System (LS1)
Version 1.0 65
While the engine is cranking, a “real-time Ellipse” will move within the Cranking table relative
to the current engine coolant temperature “operating point”. Use it as a point of reference to help
calibrate the Cranking table.
To change a value in the Cranking 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.
Once the engine starts (the ECU will detect the rapid change in engine speed) the ECU will
ignore the Cranking table and begin using inputs from the After Start Delay (see section 36).
36. After Start Delay
Once the ECU detects the engine has started, it uses the vehicle coolant temperature sensor and
inputs from the After Start Delay table to decide when to introduce the After Start Correction
Fuel. The ECU begins counting the crankshaft interrupts. When the ECU counts off the number
of interrupts defined in the After Start Delay table, for the current engine operating temperature,
the ECU adds the After Start Correction Fuel. The delay mentioned here is very, very short.
The table below shows 9 interrupts were used at –14
o
and 16 interrupts at 230
o
. One can
appreciate how quickly nine (9) or sixteen (16) crankshaft interrupts occur at an engine speed of
800 RPM.
While the engine is running, a “real-time Ellipse” will move within the After Start Delay table
relative to the current engine coolant temperature “operating point”. Use it as a point of
reference to help calibrate the After Start Delay table.
To change a value in the After Start Delay 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.