How The Injector Staging Works
Here's an answer to a question that i get asked almost every day.I noticed a few guys have been having drama's getting their head around the way the staging works & it isn't described real well in the manual either. I'll try to explain this as easy to understand as possible................
The injector staging has NOTHING to do with the secondary injectors.
The % stage value works only on the primaries & works as a percentage of the main load map.It adds fuel by adding to the millisecond value before the switch on point.
for example.......
you have the map stage set at 05",the rpm stage at 3000rpm & the % stage at 50%.Below these points you will be running only on your primary injectors.Say the millisecond value at the current load point is at 1.00m/s,with the stage set at 50% you will in actual fact be running 1.5m/s but only on the primaries.
Once you go above 05" & 3000rpm & the secondary injectors become active,the primary injectors return back to normal (1.00m/s) and all 4 injectors will be running 1.00m/s.
This is why some guys have been playing with the % stage number & the idle is affected.
Adjusting the % stage has no effect once the secondary injectors are switched on.
By moving the % stage value up it it lowers the "step" when the secondaries come in by running the primary injectors at the larger M/S value.
The larger the difference in primary/secondary injector size the higher the % stage value needs to be to get a smooth transition at the switch on point.
Most cars with 550cc primaries & 1600cc secondaries will need to be up around the 95% mark in the % stage.Once you change to a setting like that you will then have to go back & take out fuel in the lower load points to compensate.
I hope that was easy enough to understand.
RPM2 Tuner
http://rpm2racing.fotopages.com
