Precision Turbo and Engine BigStuff3 GEN3 PRO SEFI System Hardware & BigComm Software - Manual (Page 102)

BigStuff3 Pro SEFI System
Version 2.1 – February 2011 94
Boost Spark Tables 1, 2 & 3
The Boost spark tables allow the user to set the spark retard (degrees) timing as a function of RPM for
each stage. The retard timing for each stage is not additive. In other words, when the second stage
comes on it replaces the timing values of the first stage and when the third stage comes on it replaces
the timing values of the first and second stage.
To change a value in the Stage 1 Boost Spark 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.
64. Start (Starting) Line Timing
The GEN3’s Starting Line Timing feature is primarily focused at stick shift and turbo charged vehicles
(turbo cars with stick or automatic transmissions). This feature allows the engine to build boost at the
starting line. The Starting Line Timing feature can be used in conjunction with the 2-Step to maximize
starting line performance!
How to Use With Stick Shift Cars - For stick shift cars, the ignition timing needs to be retarded in
order for the engine to build boost at the starting line (with the clutch in).
If this feature is used with the 2-Step, make sure that
Boost_Parameters RPM input is set 1,500 RPM
below the 2-Step RPM enable point. Once the TPS and RPM Boost Parameters criteria are satisfied
(and there is 12 volts supplied to the two step wire), the ECU will use the timing values from the
Starting Line Timing table. If the RPM and TPS criteria are not met (and/or 12 Volts is not supplied to
the two-step wire), the ECU will default to the timing values in the main spark map. The values in the
main spark map may not allow the engine to build boost, so it is important to properly configure the
relationship between the Boost Parameters RPM and TPS criteria and the 2-Step RPM. It takes +12V
to activate the 2-Step.
How to Use With Automatic (transmission) Cars – For automatic cars, the ignition timing should not
be retarded. You want to use whatever ignition timing values the engine requires to build boost and
make the car leave hard.