Injector Offset Adder - Clarification

[jthompson122183]

Is it the same for both xdf I haven't worked on eextra for a few. Or is steveo different?

[Terminal_Crazy]

Steveo's are correct i think
EEXTRA has columns swapped over which had me confused. (Not very hard)

Mitch

[jthompson122183]

Steveo's are correct i think
EEXTRA has columns swapped over which had me confused. (Not very hard)

Mitch

I'll make a note of that. I started with a old version of eex 2.something I think, Bear with as I'm still quite new to learning this stuff. If you have any recommendations or know anything else that is off or know what something is speak up, I'm all ears. My goal with eextra is when comparing files we don't see "Item Not Defined" anymore

[Terminal_Crazy]

Cool.
I'll keep my eyes posted then.

Thanks
Mitch

[Terminal_Crazy]

What i was actually asking was what does the adder actually do?

add the usec time to the BPW or deduct it from the calculated time.

ie. If my bpw was at 1.952 ms and I add 100 into the (1952usec) table would it deduct 100usecs worth of fuel (the amount of injector dead time) from the calculated BPW ??


Mitch

[troutdog311]

Terminal did you ever find out exactly what effects this has. I have played with it many times but didn't see much if any difference. Some bins have it 381.48 BPW then gradually getting lower to 30.52 BPW while I believe it's the corvette has nearly the same though has 228.88 BPW between 793 - 1464 Adder columns.

[troutdog311]

I have been reading somethings about short pulse adder in HPTuners. I believe it's the same as our adder just called something different in HP. One guy briefly explains it like this.
The short pulse adder is meant to linearize the injector characteristic for very short pulsewidths, where simply using the injector flowrate gives the wrong result and the injector does not inject the amount of fuel the PCM thinks it is. I don't know and still diggging

[Terminal_Crazy]

Hi troutdog311
I've read a bunch of interesting articles (by Greg Bannish & Injector Dynamics) but not had time to play yet.
The injectors take a short time to open and then fuel starts to flow taking a time until it stabilises to the injector flow rate.
(This is a curve from zero upto where the flow/time straightens out).
I understand the concept but not which way round the figures work.
In my tune they were all set to zero and presumably adjusted around.

My thoughts are:
If the injector takes 500-usec to open and 1000-usec before flow stabilises.
In Open loop:
With a BPW of 1000-usec we have 500-usec of no flow and 500-usec of partial flow.
with a BPW of 1500-usec we'd have 500-usec of no flow 500-usec of partial flow & 500-usec of stable flow.
so the adders are to make up the shortfall.

I realise I have been viewing the logs whilst in Closed loop so the PCM would have already compensated for this.

Thanks
Mitch