Injector Phase???

[jbrito]

Hi people,

I'm currently running a ECU Master on my 91 325i E36 (m50 non vanos), and i dont really know the correct injector phase for fully sequential injection on my engine.

This is my setup right now

Ignition Event #1 -> Cilinder #1 (G8)
Ignition Event #2 -> Cilinder #5 (B8)
Ignition Event #3 -> Cilinder #3 (G9)
Ignition Event #4 -> Cilinder #6 (G1)
Ignition Event #5 -> Cilinder #2 (G16)
Ignition Event #6 -> Cilinder #4 (B16)

Injector 1 Phase -> Ignition Event #1
Injector 2 Phase -> Ignition Event #5
Injector 3 Phase -> Ignition Event #3
Injector 4 Phase -> Ignition Event #6
Injector 5 Phase -> Ignition Event #2
Injector 6 Phase -> Ignition Event #4

is this right?

Thanks

[RHD]

as far as i understand that will fire the injectors on the first trigger tooth so approximately 65 degrees (trigger angle) BTDC on the compression stroke

or about 420 degrees before the intake stroke starts

[Jadzwin]

What is your ignition output offset ?

[jbrito]

Here is my ECU file,

https://www.dropbox.com/s/gsp3g9juidcmwj2/122.emu?dl=0

My ignition offset is set to 0 i think

[jbrito]

as far as i understand that will fire the injectors on the first trigger tooth so approximately 65 degrees (trigger angle) BTDC on the compression stroke

or about 420 degrees before the intake stroke starts

So this way my injectors are firing when the cylinder is on the compression stroke rather than on the admission stroke?

[RHD]

yes essentially they are firing just before the spark happens which is at the end of the compression stroke. You can assign each one to the opposite cylinders if you want it to start injection just before the intake stroke.

This exact point before TDC is actually defined by the primary trigger angle setting. You can assign each phase to different cylinders to make it start to inject sooner or you can use the injection offset to make inject later.

[jbrito]

So that way the correct setup is:

Inj1 - Ign6
Inj2 - Ign5
Inj3 - Ign4
Inj4 - Ign3
Inj5 - Ign2
Inj6 - Ign1

Is this correct for the injector to open when the admission stroke begins?

This is really getting me confused.....

[Kurt]

I haven't looked at it in a while, but if nothing has changed in the firmware then this is how it works:

viewtopic.php?f=19&t=154

With injection offset of zero, the injector that's assigned to Ignition Event 1 will open at the point of 1st trigger tooth. So, in your case, the cylinder you have set to ignition event 1 is at TDC compression at 60° after tooth 9. (tooth 9 is the 10th counted tooth after the missing section, EMU starts count at 0) With injector offset at zero, your injectors open at tooth 9, which is 60° BTDC compression. Injector timing works from the sequence of ignition events, not current ignition angle.

Injector offset moves injector open point later, so in your case if you were to set this to 60, the injector will open at TDC compression. If you want to move this point to TDC exhaust, you would change the injector phase to a different ignition event. In order to give you a range of retard or advance relative to TDC exhaust, you will want to move the injector phase up one ignition event and set injector offset to 180+trigger angle. In the case of a 6 cylinder, that would be moved up two ignition events and injector offset 120+trigger angle.

To get proper starting point for injector phase before moving up to next ignition event, first set these to the coil firing order. So, if ignition event 1 is set to coil 1 (cylinder 1), then injector 1 will be set to ignition event 1. Injector 2 will be set to coil 2 firing event, which would be 4. etc.. Once these injector phases are set, just change the ignition even up 1 on each injector. So, if injector phase 1 is set to ignition event 1 then change this to 2. If injector phase 2 is set to ignition event 4 then change this to 1. etc.. Then enter 180+trigger angle in injector offset. In your case, this would be 240. The issue in your case is you will only have 15° available to retard injector timing from TDC exhaust since the injector offset option only goes to 255. If you need to set this beyond that point for good idle, you will want to go back and move your injector phase up two ignition events and set offset to just the trigger angle.

There are two unfortunate things with how the EMU does injector timing. First, there's no injector advance map. Second, injection point is start of injection instead of end of injection. So, optimized injector timing for idle will not be optimized for start or cruise or WOT.