Precision Turbo and Engine BigStuff3 GEN3 PRO SEFI (LS1) System Hardware & BigComm Software User Manual
Page 62
BigStuff3 Pro SEFI System (LS1)
Version 1.0
61
The Fuel table uses Volumetric Efficiency (VE) values in each of the 256 cells in the table.
Volumetric Efficiency is the measure for how efficient the engine is operating at a given engine
speed and load combination. The efficiency of the engine is nearly perfect at a value of 100.
Volumetric Efficiency (VE) is highest at peak torque.
The Fuel table allows the user to input desired (VE) values for sixteen (16) engine speed (RPM)
and sixteen (16) load (MAP or TPS) combinations. The X-axis represents engine RPM and
allows for 16 inputs and the Y-axis represents engine load and allows for sixteen (16) inputs as
well. The X and Y-axes are configurable. For information on how to configure the X and Y-
axes see
While the engine is running, a “real-time Ellipse” will move throughout the Fuel table relative to
the current RPM & Load “operating point”. Use it as a point of reference to help calibrate the
Fuel table.
To change a VE cell value in the Fuel table, move the cursor using the PC’s mouse or the arrow
keys to the cell to be changed. Click on the cell and type a desired VE value (from to 15.0 to
200) and hit “Enter” to save the change.
To make changes to multiple cells simultaneously, left mouse click and drag the cursor across
the cell range to be changed. Release the left mouse button and a secondary drop down screen
will appear outlining three potential “cell fill” options
• Fill – Choosing “Fill” will open a secondary drop down- screen which allows the selected
cells to be changed to the value inputted into the window.
• Multiply – Choosing “Multiply” will open a secondary drop down-screen which allows
the values of the selected cells to be changed by the ” Multiply” value inputted into the
window. For example, if the values in the cells selected are 13 and the inputted
“Multiply” value was 80%, the new cell values would be 10.4.