Join Date: Mar 2008
Location: Kapuskasing Ontario Canada
Mentioned: 2 Post(s)
D-J Method and α-N Method:
When the engine load is light like at idling or low speed, the ECU determines the injection quantity by calculating from the throttle vacuum (inlet air pressure sensor) and engine speed (crankshaft sensor). This method is called D-J method (low-speed mode). As the engine speed increases, and the engine load turns middle to heavy, the ECU determines the injection quantity by calculating from the throttle opening (main throttle sensor) and the engine speed. This method is called α-N method (high-speed mode).
For high altitude operation, it helps that the Versys is calibrated with a lean low end, especially near 2800 rpm... Without any Power Commander fuel corrections, air/fuel ratio reaches a lean peak at 2800 rpm (~14.5:1), falls progressively richer to a dip at 4100 rpm (~12.8:1), leans back up (~13.5:1 @ 4500-5000 rpm), then richens considerably to 5500 rpm (~12.2:1) and up to redline (~11.5:1).
Last edited by invader; 09-16-2013 at 10:10 PM.