Originally Posted by
kingtal0n
Before you play much with transients get the VE table very smooth and finished almost.
The VE table can contain information regarding transient behavior. For ex between 60KPA and 80KPA You will be richer whether its a steady state or a transient. So tune those regions in the VE table as if they are part of transient fueling. It will help you avoid needing to increase the transient fuel after the fact, and rely more on the VE map to become rich.
In fact its a little advanced tuning theory but I think you can handle it- look at my VE table and notice the way I've got extra fuel coming in for 60-85KPA. Those regions are pre-PE mode and yet they enrich leading up until the PE kicks in, after which the VE table flattens back out.
This is because
A. don't depend on rate of change transients to enrich you prior to PE Mode. This allows you to relax the PE mode restrictions, they can be 'late' and you still get enrichment as needed with pressure increase from the VE table.
B. The OEM ecu pretend to use a closed loop leading up to PE- but closed loop is 14.7 and sometimes you want 14.4 or 14.2 and other times you want 13.3 or 12.8. So instead of trying to fine tune the PE mode activation and deal with differences at various RPM (they PE mode "turns on" and sometimes it can miss its mark at 'other' rpms) simply tune the VE map like a stand-alone ECU (whatever A/F @ load point you wanted) and leave PE off until some absolute point of no return where you can be assured the enrichment is worthy of the conditional.