Trouble tuning with EBL P4 Flash

[djmac]

Hi,
I have a bit of a Hybrid setup. I have a 1982 Jeep J10 with a Ford BB. I upgraded my ECM to an EBL P4 Flash and added an AEM AFR guage. I attached the engine specs below. It has 85 pd Siemans injectors and a 1000 cfm Holly throttle body. I have a very basic knowledge of tuning and I am working with an experienced tuner online recording datalogs from Dymanic EFI's WUD app.
The problem is that my Tuner has made multiple attempts Via VE tables to reduce the fuel coming in without success. I then started reducing the fuel pressure from 64 psi and eventually down to 30 with very little change in the fuel delivery. I also change my WB 02 sensor to be sure I am getting accurate data from the W/B Below is a cut and paste of a recent email:
Below is timeline data:
6.26.23.dat has an overall AFR average of 11.827, with fuel pressure set to 43 PSI.
6.30.23c.dat has an overall AFR average of 11.937, with fuel pressure set to 43 PSI.
7.7.23e.dat has an overall AFR average of 11.925, with fuel pressure set to 35 PSI.
I would like to think lowering the fuel pressure to 35 PSI would have changed the AFR's more, apparently not. I would like to think that the change in the injector flow rate from 80 lb/hr to 85 lb/hr would have changed the AFR's more, apparently not.
I'm not sure what the next step is? The updates to the .bin files have not changed AFR's as expected. The change in fuel pressure has not changed the AFR's as expected.
I am open to any suggestions this board might have to offer. If I can offer any more details please let me know.
TIA
Dan

[steveo]

not overall afr average, that isn't really a reliable way to compare fueling changes. use an analysis with table cells and compare difference between certain cells that have lots of data populating them, that'll give you a better idea if your afr is being affected. if you just use overall average and take 10 different drives you'll get 10 different results.

when analyzing fuel you'd best filter out some stuff, for example you should filter out data with TPS < 5 or something so you discard deceleration fuel cutoff events (being in DFCO will pull your global average leaner for the duration of the cutoff), discard data below proper coolant temperature, and of course filter out data with closed loop in it because the ECM will just trim it back to wherever

changing the injector flow rate from 80 to 85 should yeild around 6% less fuel (for example if you had a 12.0:1 afr it should now be around ~11.3)

changing the fuel pressure is more complicated however going from 43 to 35 psi should give you around 10% less fuel (because changing fuel pressures alters your fuel by roughly the square root of the old pressure divided by the new pressure, it's not a linear change like you'd think)

those two things being changed at the same time should give you around 16% less fuel or so which in closed loop would be corrected very quickly

its possible your ECM uses closed loop overall trims or cell exit trims to affect wide open throttle too, therefore adjusting out all your changes at the same time you're measuring them

changing the fuel pressure from 60 to 30 would remove 41% of fuel though which should not be adjustable by closed loop and the engine should barely run

[djmac]

[QUOTE=steveo;99406]not overall afr average, that isn't really a reliable way to compare fueling changes. use an analysis with table cells and compare difference between certain cells that have lots of data populating them, that'll give you a better idea if your afr is being affected. if you just use overall average and take 10 different drives you'll get 10 different results.

Steve thanks for your input. It makes a lot of sense. I did want to ask this question though. Given this is my first experience with the WUD app is it possible that I am somehow mishandling the bins I am receiving and loading? I ask this because after loading the bins my seat of the pants dyno doesn't notice much in the way of performance changes. It's almost like I reloaded the same file. I can't see how I could have done that because the WUD app greatly simplifies the whole process compared to how I used to do it with Tunerpro and removing the Memcal to burn a new file. The WUD app correctly displays the new file name as well so it doesn't seem likely that file management is the issue but I thought I would throw it our there in case others has had the same experience.

[dave w]

not overall afr average, that isn't really a reliable way to compare fueling changes. use an analysis with table cells and compare difference between certain cells that have lots of data populating them, that'll give you a better idea if your afr is being affected. if you just use overall average and take 10 different drives you'll get 10 different results.

FYI my efforts with djmac have been pro bono

Typically gross adjustments with Injector Flow Rate or Fuel Pressure "will move the needle for rich vs. lean corrections."

Looking for new eyes / new ideas on what next step might be.

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[djmac]

[QUOTE=dave w;99414]FYI my efforts with djmac have been pro bono

Typically gross adjustments with Injector Flow Rate or Fuel Pressure "will move the needle for rich vs. lean corrections."

Looking for new eyes / new ideas on what next step might be.

I would like to add that Dave has been amazing and he has the patience of Job with this Newb!