1700cc Injectors on factory E38 ECU

[Zachbecken]

I am trying to help out a friend with tuning on his 2010 Camaro with a 7.0L LS, Procharger and ID1700Xs. It is currently on 93 but plans on running E85 most of the time and targeting around 20psi hence the 1700cc injectors. Fuel pressure is set at 58 PSI. All the mechanical work was done at another shop and it has been to two separate tuners trying to get it to run right. Both other tuners recommended going to a standalone ECU. I figured I would offer him some help and see if I could manage the tune without the standalone and gain some knowledge at the same time as this is a bit above what I normally tune. My current issue is getting it to run at a reasonable AFR. It idles around 13.5 and it spikes to 10ish with any throttle input. The injector data was scaled at 45% as was the stoic and IVT terms. I have been attempting to cut the MAF table and raise the base running airflow to try to get it to lean out. The only luck I have had in doing so completely kills the MAF curve if it gets close to 14.7 at idle. Usually when I chase my tail like this it ends up being a physical issue and not a tuning issue which is why I have recommended that he either only tunes on E85 or gets smaller injectors, nut I figured I would reach out and see if anyone has some better informed advice. I have attached a log file and the current tune, however the current tune is by no means a finished product and once this issue is solved will be polished. Any input would be appreciated

[gtstorey]

What does the fuel delivery system look like? Sounds like good case for a referenced fuel system if it's not.

[hjtrbo]

Worth considering dropping that fuel pressure down to 3bar. That'll give you a little more resolution in the non linear region of the injector. Also check your not clipping on your min pulse width.

[edcmat-l1]

Not just worth considering, that's the way it should be done.

Injector data is setup as if it's dead headed and I'd bet it's not.

VVE is not correct numerically. You're not going to be able to "MAF only" tune this car.

You're logging a bunch of stuff that doesn't matter.

Stoich isn't set correctly.

[Zachbecken]

Not just worth considering, that's the way it should be done.

Injector data is setup as if it's dead headed and I'd bet it's not.

VVE is not correct numerically. You're not going to be able to "MAF only" tune this car.

You're logging a bunch of stuff that doesn't matter.

Stoich isn't set correctly.

What about the stoich is incorrect? The way I understood it was to scale the injectors whatever percentage is taken out of the flow rate table needed to be added to the stoich table and IVT tables

[Zachbecken]

What does the fuel delivery system look like? Sounds like good case for a referenced fuel system if it's not.

It has a Fore triple pump. 3 of these
https://www.radiumauto.com/Walbro-F9...Pump-P412.aspx

[gtstorey]

It has a Fore triple pump. 3 of these
https://www.radiumauto.com/Walbro-F9...Pump-P412.aspx

And how is it regulated?

[Zachbecken]

And how is it regulated?

boost referenced return style fuel pressure regulator with the regulator after the fuel rails

[edcmat-l1]

All your data is setup for a dead head system.

[Zachbecken]

All your data is setup for a dead head system.

So I figured out my stoich problem. I only multiplied it by 1.5 instead of 2 so thats now fixed. As for the fuel system being set up for a dead head, what parameters would need to be changed?

[Zachbecken]

All your data is setup for a dead head system.

From what Ive been reading I need to make the tables for IFR and offset vs press vs INGV constant across the whole table using the injector data at 300kpa. Is this correct?

[blindsquirrel]

adapting-fuel-injector-data-with-a-manifold-referenced-fuel-pressure-regulator.pdf

Mr. B hisself I believe has posted that file here somewhere, can't find the thread it came from though.

300kPa column if that's the base pressure you're using, yes. Would be 400(408)kPa if 58psig.

[Zachbecken]

I was able to get the fueling data properly adjusted, however I am still having issues with fuel delivery. The AFR is all over the place with zero input. sometimes it will idle at stoich, sometimes rich, sometimes lean. I have attached a log file showing this. Fuel pressure is consistent during the run. If its not the tune my only thought is a clogged injector or bad ECU. any input would be appreciated.

[blindsquirrel]

Why does the log show a P0103 when the tune file does not have the MAF failed?

[blindsquirrel]

B1S1 is shorted to ground? (stuck at 3 mV)

[blindsquirrel]

screenshot.18-11-2024 14.51.48.png screenshot.18-11-2024 14.52.24.png screenshot.18-11-2024 14.54.45.png

[Zachbecken]

B1S1 is shorted to ground? (stuck at 3 mV)

sensor is pulled for the wideband

[Zachbecken]

screenshot.18-11-2024 14.51.48.png screenshot.18-11-2024 14.52.24.png screenshot.18-11-2024 14.54.45.png

I fixed the U0109 code to report no MIL light as it no longer has a FPCM installed, I also changed the post CAT O2 sensor count to 0, however I do not have the option to disable catalyst test in the engine diag section as it is not present in my tune. I have included a screen shot as to what my options are in that window.

As for the P0103 code, I will need to double check as have been switching between MAF enabled/disabled to work on the VVE tables and I may have forgot to clear the code

Screenshot 2024-11-18 151130.png

[Alvin]

That is a pretty advanced project for a new tuner.

Getting the injectors and basics setup correct are going to be first step.

You also need to get the VVE going.

There is a Min fuel increment in the transient section that becomes a problem with large injectors. You can zero that out. But there is a lot in that file that needs to be addressed. For instance PE is is setup to be pretty damn dangerous for boost. Shoot for 1.22 at a minimum..

[Zachbecken]

That is a pretty advanced project for a new tuner.

Getting the injectors and basics setup correct are going to be first step.

You also need to get the VVE going.

There is a Min fuel increment in the transient section that becomes a problem with large injectors. You can zero that out. But there is a lot in that file that needs to be addressed. For instance PE is is setup to be pretty damn dangerous for boost. Shoot for 1.22 at a minimum..

Thank you for the catch on the PE table, I had it set up for NA. I have been attempting to get the idle/ part throttle to read consistent before I attempt anything approaching a power pull which is why the tune is not polished. This vehicle has been to 2 other tuners already without any luck and I didn't want to sink a bunch of time attempting to get it right just to find out it has a clogged injector or bad ECU.

As for the VVE tables, I have always tuned the MAF table first then moved to the VVE, should I be reversing that process on this vehicle? Also would the VVE tables not being correct cause a large swing in AFRs at a constant RPM and load?