Precision Turbo and Engine BigStuff3 GEN3 PRO SEFI System Hardware & BigComm Software - Manual (Page 47)

BigStuff3 Pro SEFI System
Version 2.1 – February 2011 40
Hardware Configuration Table
The Hardware Main Configuration table is relatively self-explanatory. Working from the top of the
table, select the parameters in the screen print above as follows:
 Select the number of cylinders the engine has.
 Select whether system will operate using a speed density (engine speed and engine load) or
Alpha N (throttle angle and engine speed) algorithm. The majority of the engine applications
use the Speed-Density control algorithm. If the camshaft duration exceeds 260
0
at .050” lift,
the Alpha N control algorithm should be considered. Contact BigStuff3 if you are uncertain
whether Speed Density or Alpha N control is best for your application.
 Select the fuel feed back control configuration. “Open Loop” control uses the oxygen (O2)
sensor feedback to ensure the user defined air/fuel ratio is achieved. “Open Loop” control
does not use the oxygen sensor feedback to ensure the desired air/fuel ratio is achieved. In
most cases, tuners will set the initial calibration, and perform subsequent fine tunes in “Closed
Loop”, but will race with the O2 sensor turned off (“Open Loop”). Note: The air actual
air/fuel ratio will still be displayed and recorded (via the Replay feature) while in “Open Loop”
mode.
 Select the type of Throttle Position Sensor (TPS) being used (to output throttle angle to the
ECU). The TPS is located on the side of the throttle body, at the end of the throttle shaft. GM
style TPS sensors have a .5V to 4.5V output and Ford sensors have a .9V to 4.5V output.
 Select the Manifold Absolute Pressure (MAP) sensor setting for the application. Make sure
the appropriate MAP sensor has been purchased for the boost pressures that the engine will
see. For normally aspirated engines, a 1 BAR MAP sensor should be used and the 1 BAR
MAP setting should be selected. For blown or turbocharged applications with boost pressures
up to 15 PSI a 2 BAR MAP sensor should be used and the 2 BAR MAP setting must be
selected. For boost pressures up to 30 PSI, a 3 BAR MAP sensor should be used and the 3
BAR MAP setting should be selected. For boost pressures up to 52 PSI, a 4 BAR MAP sensor
should be used and the 4 BAR MAP setting should be selected. For boost pressures up to 60
PSI (gage) a 5 BAR MAP sensor should be used and the 5 BAR MAP setting should be
selected. If a 5 BAR MAP sensor is going to be used, contact BigStuff3 to make your