Volunteers needed for E38/E67 Calc.VET project.

[opcode]

Now that I have the logging sorted out, what now? Get a 30+ min log and post it w/ my tune?

[joecar]

The IFR table uses delta pressure... calculated from rail pressure and MAP.

That's what I was hoping... his IFR being flat confirms this... but I want to know that his FPR is referenced.


Mean Green Z28: is your FPR manifold referenced (is it close to the rails, and has a return tube going back)...?


What is your measured rail pressure (measure with reference hose temporarily disconnected, i.e. FPR exposed to barometric pressure)...?

[joecar]

What are some of those ^ parameters used for, if the fuel pump has variable speed, the FPR should smooth this out... right?

( I see that variable speed pump is set to No in this case... but what do you do when it is set to Yes...? )

[joecar]

Now that I have the logging sorted out, what now? Get a 30+ min log and post it w/ my tune?

Drop the pid SAE.TP and replace it with GM.ETCTP, this brings the pid channel count up, to 31;

Depending on whether SAE.LAMBDA works prooperly, we'll drop these pids:
- E38.AFRATIO if SAE.LAMBDA works ok, or SAE.LAMBDA if it does not,
- GM.ACCEP,
- SAE.SHRTFT1,
- SAE.SHRTFT2,
- SAE.VSS,
- SAE.ECT,
this should bring the pid channel count down to 24.

Did you do that ^

Are we going to log MAF [g/s] or are we SD...?

So are we going to use STFT's instead of LTFT's (STFT's are too dynamic, LTFT's are more filtered)...?


Take a 20 minute log, see if you can get rpm into 4000-5000 range (just a few times), let's see what we get.

[joecar]

From your log in post #84 above

Bret scaled CL_STFT_MAF_VVE_REV_0038b.efi

I see that the WB goes overly lean after each large throttle closure... I see DFCO is disabled.

I see the STFT's trending up, pretty much pegging... we might want to see what the LTFT's are doing.

[Mean Green Z28]

That's what I was hoping... his IFR being flat confirms this... but I want to know that his FPR is referenced.


Mean Green Z28: is your FPR manifold referenced (is it close to the rails, and has a return tube going back)...?


What is your measured rail pressure (measure with reference hose temporarily disconnected, i.e. FPR exposed to barometric pressure)...?

the pressure you see is from the in tank controller, nothing at the rails .. it's a return-less system.

What are some of those ^ parameters used for, if the fuel pump has variable speed, the FPR should smooth this out... right?

( I see that variable speed pump is set to No in this case... but what do you do when it is set to Yes...? )

Not quite sure of how it all works. We played with settings until we found that we can adjust the HI fueling pressure and it followed PE mode

From your log in post #84 above

Bret scaled CL_STFT_MAF_VVE_REV_0038b.efi

I see that the WB goes overly lean after each large throttle closure... I see DFCO is disabled.

I see the STFT's trending up, pretty much pegging... we might want to see what the LTFT's are doing.

LTFT is turned off as we saw that going to 0 at WOT/PE mode so Bret played with the VVE more ... then we played with the Intake Temp vs. fueling table to account for temperature changes through winter/etc.. And Bret turned off DFCO.

If there's other/better ways of doing it, I'm all ears! This was both our first time playing with a E38

[joecar]

the pressure you see is from the in tank controller, nothing at the rails .. it's a return-less system.

Then your IFR table is incorrect (it cannot be flat)... this will cause fueling to be wrong (ECM over-calculates the injector pulsewidth for non-WOT conditions).

Not quite sure of how it all works. We played with settings until we found that we can adjust the HI fueling pressure and it followed PE mode

Which settings (table id #) did you play with...?

LTFT is turned off as we saw that going to 0 at WOT/PE mode so Bret played with the VVE more ... then we played with the Intake Temp vs. fueling table to account for temperature changes through winter/etc.. And Bret turned off DFCO.

LTFT's may go to zero at WOT, that's ok. I was mentioning DFCO to make sure that it wasn't DFCO that was causing the lean peaks after throttle closes.

If there's other/better ways of doing it, I'm all ears! This was both our first time playing with a E38

It's not a matter of other ways... we have to sanity check what is currently running, make sure we understand the model (for example, returnless fuel system uses an un-referenced FPR which requires the IFR table to be sloped.

Yes, E38's seem very strange after working with LS1 and E40.

[joecar]

Your B4001 IFR table:



This ^ flat IFR table is for a MAP-referenced FPR (i.e. FPR has hose connecting to intake manifold) (this is a return fuel system).

For a un-referenced FPR (returnless fuel system) the IFR has to be sloped (actually it goes as sqrt of pressure ratio).


400 kPa (which the ECM has to interpolate) corresponds to WOT with no boost.
< 400 kPa correspond to boost.
> 400 kPa corresponds to part throttle conditions.
468-488 kPa corresponds to closed throttle.

Also: you have to measure rail pressure to correctly shift/scale the IFR table.

[Mean Green Z28]

Hmm wonder if we have to start all over. You think it's why we're having trouble fine tuning it? And also the wild crazy curves and slopes on VVE table?

I'll be going back to a smaller 6766 Precision turbo and ditching the 7875 On3 turbo this year ... I'd like to enjoy it around town than be a highway warrior with high top end numbers. Maybe I'll change things around a bit to get things a bit better mechanically (like MAF locations etc.). I just don't feel like starting all over but if that's what it'll take, it'll have to be it.
The truck barely gets off from a stop and can't ever do a burnout haha but I'm hoping it's the combo of the 78 and 4L80E and 3.42 gearing that's giving me the bad low end

Sent from my SAMSUNG-SM-G900A using Tapatalk

[Mean Green Z28]

Your B4001 IFR table:



This ^ flat IFR table is for a MAP-referenced FPR (i.e. FPR has hose connecting to intake manifold) (this is a return fuel system).

For a un-referenced FPR (returnless fuel system) the IFR has to be sloped (actually it goes as sqrt of pressure ratio).


400 kPa (which the ECM has to interpolate) corresponds to WOT with no boost.
< 400 kPa correspond to boost.
> 400 kPa corresponds to part throttle conditions.
468-488 kPa corresponds to closed throttle.

Also: you have to measure rail pressure to correctly shift/scale the IFR table.

I have sent InjectorConnection an email requesting the IFR table on these 80lb injectors. I know we were having issues with all this at the beginning when we decided to scale the tune. We were supposedly hitting the 512g/s limit I was told and what we ended up with was a bandaid I guess you could call.