Low PW Compensation

[Flat_Rate]

all these updates and still??

[blakebonkofsky]

It was added in 2.27 FW and above, 3 months ago. You just need to update and enable the feature.

[JimKden]

It was added in 2.27 FW and above, 3 months ago. You just need to update and enable the feature.

Where is it located in ESP? I have 2.27 FW installed and 2.00.35 ESP, can't locate it.

[blakebonkofsky]

It was added in 2.27 FW and above, 3 months ago. You just need to update and enable the feature.

Where is it located in ESP? I have 2.27 FW installed and 2.00.35 ESP, can't locate it.

Main Setup under the Fuel tab. I believe it's called "Short Pulse Width Adder" or something like that.

[JimKden]

Thank you. I am sure I looked for it, must have had my eyes closed!

[Flat_Rate]

Am i not understanding this correctly??

The info i have from Injector dynamics is in MS vs a Percentage

Haltech table is MS vs MS it appears...

Any clues to how to change this up or convert the data to work with haltech?

[Flat_Rate]

Would it be correct to assume that its a percentage correction of time and not flow??

so say at .200MS its adding 88% ( like showed in OP)

so to convert to time would be .376MS?

[HaltechMatthew]

You cant use percentage because it is not a percentage you are correcting for it is an accrued amount of full open flow injection time. Their data is not so useable in that format. At best you could say it is a percentage of that commanded injection time, do the sums, and enter that corrected injection time amount under that value.

To explain short pulse width correction in short, you are commanding a certain amount of fuel on the basis that the world is perfect. In reality the injectors do not crack open instantly. As the pintle begins moving some fuel flows between when you start to open and it opens fully, and when it starts to close and it closes fully and this is of course non-linear at not the true full open amount of flow. If we are commanding a very small amount of injection time that is lets say equal to this amount of time to open and close you obviously did not get the amount of fuel you asked for, you got much less because it is not in open flow. So this is what the table is for, to correct for the amount of time to compensate for the opening and closing of the injector when it is not linear in flow. Truth is this in in effect all of the time even it high injection time, just the amount if almost inconsequential to the tune.

The bigger question is how you find this data. The even shorter answer is you cant. Without having a flow test machine to measure it you are only guessing, but by guessing you will already get it closer to ideal operation than doing nothing at all.

So, fake it until you make it.

[Flat_Rate]

Talking to your tech support on the phone, they had suggested to use a generic fuel correction table with the effective pulse width as the axis and input the data that way..

I can tell you that it ran absolutely terrible this way..

i will do the math and add/subtract the percentage from the pulsewidth times given and see how that works.

[JimKden]

If anyone is using the ID 725 injectors, the attached file was sent to me from ID. This is not on the ID website. I requested the info and they developed the numbers. The file may not make it to their website because the ID725 is no longer being sold and other info for them is not found anymore.

[Flat_Rate]

If anyone is using the ID 725 injectors, the attached file was sent to me from ID. This is not on the ID website. I requested the info and they developed the numbers. The file may not make it to their website because the ID725 is no longer being sold and other info for them is not found anymore.

so have you used this data?

I assume you are having to convert the percentage to a time as well?

[JimKden]

Not used yet, it came in yesterday. I need to review the discussion above. It looks to be in the same format as for the larger injectors.

[JimKden]

I see the latest firmware/software now has "effective pulse width" parameter, so the data from ID should be able to be used. The fuel pressures in the id data though are the differential pressure across the injector.

[Flat_Rate]

I see the latest firmware/software now has "effective pulse width" parameter, so the data from ID should be able to be used. The fuel pressures in the id data though are the differential pressure across the injector.

The fuel pressures are there for the different voltage offsets??

The values for the low pulse width are a percentage of time..

Not sure i follow what you are saying

[JimKden]

The fuel pressure given by ID is the differential pressure across the injector, not the absolute fuel pressure given ESP. Because the table in ESP does not have a second axis available, I used a row of voltage values where I most often operate. I interpolated for a set of values to a diffewrential pressure I see at low loads. That's the close as I could see to obtain at present. You'll need to run a spreadsheet to find the time to add. Not saying this is the best but it is as I see it for now.