What the table is
Some engines run two sets of injectors: a primary set that handles idle and cruise, and a secondary set that joins in when the engine needs more fuel than the primaries can deliver. Base - Stage 2 holds the raw injection time delivered through that second stage.
It only appears when the fuel tuning method is Injection Time. In that method you tune pulse widths directly rather than volumetric efficiency, so each stage needs its own table of times.
Tuning tips
- Tune the primary base fuel table first, so you know how the engine behaves before stage 2 takes a share.
- Watch the wideband closely through the region where stage 2 starts contributing. That's where lean or rich steps appear.
- Remember the injection times here are raw, so if you change the stage 2 injectors, this table needs retuning.
More on fueling in fuel tuning and target lambda.
