FIC Injector Data

[ferocity02]

So I dropped FIC's B3701 offset table by 20%, retuned the VE table, and I believe the rich decel issue has been cured.

But now the question is, when does one stop modifying the injector data?

For example, I could drop B3701 which will lean it out across the board, and then raise the VE table to richen it back up, and vice versa. So at what point do you hold the injector data constant and use the VE table to do the adjusting?

If the injector data is way off, it could still be tuned with the VE table within reason, but the calculated airflow would not be representative of the real airflow.

Am I looking into this too much?

[5.7ute]

So I dropped FIC's B3701 offset table by 20%, retuned the VE table, and I believe the rich decel issue has been cured.

But now the question is, when does one stop modifying the injector data?

For example, I could drop B3701 which will lean it out across the board, and then raise the VE table to richen it back up, and vice versa. So at what point do you hold the injector data constant and use the VE table to do the adjusting?

If the injector data is way off, it could still be tuned with the VE table within reason, but the calculated airflow would not be representative of the real airflow.

Am I looking into this too much?

Injector data "should" be left alone as it is based on the mechanical properties of the injectors being used. However this depends on the reliability of the data you have been given. I am not saying that the data you have is erronous, but there have been some doubts as to where that data you have has been generated.
The only definitive way you can test the data without the neccesary equipment is to tune the vehicle with stock injectors & data. Swap them back to the new injectors & data & look for changes in the resulting AFR's.
The log you sent should answer some questions once I get an hour or so to go through it.

[ferocity02]

So when I swapped the injectors and didn't change anything else except for the injector data, the fuel trims went from +/-1% to -6%-max negative in decel. I tried adjusting the MAF table but it was always rich in decel. Reducing B3701 was the only cure I found.

Then I switched to COS5 2bar OLSD hoping it would help but had the same issue just with the VE table instead of the MAF table.

I am aware of the doubt about FIC's injector data, hence not trusting their data completely. My tuner is certain the injector data is incorrect as well.

Thank you for the help!

[5.7ute]

That is certainly pointing to bad data.
I posted a while ago on here a way I thought B3701 could be tuned in from a good known tune with accurate data. I will try find it & post a link.

[5.7ute]

Take a look here.
http://forum.efilive.com/showthread....ighlight=b3701
This is just the basics of it. There will be calculated pids to write to get it to work, as well as a lot of filtering to remove small pulse adder errors etc.
Also I should note that a offset issue should occur throughout the tune, not just in decel. If only decel is the culprit small pulse adder could be the problem.