LSA Boost/RPM/Torque Limit

[Lightning Performance]

Hey Guys,

I've got a issue that has got me a bit stumped.

2016 Holden HSV GTS LSA E67, manual vehicle, 2 bar SD upgrade.
Mods include 2650 blower, 1500cc injectors, Cam, exhaust, Interchiller, KPM intank multiple fuel pump module upgrade (returnless) Harrop 115mm Throttle Body etc.

Started to dyno the vehicle last week, first pull maxed out the 90LB Deatschwerks injectors - engine turned 5800 RPM 128% DC, 230KPA manifold pressure. All good.

Today I installed the new Excess 1500cc injectors and scaled the tune to suit the larger injectors.
Added approx +20% to the VE table to get the fuelling close then dialled in the VE table at light loads.

Attempted a full power sweep test and I seem to have some sort of limiter/cut happening at approx 3900 RPM.
Incidentally, this would be close to where the factory style Bi-Modal exhaust opens up.
Have noticed in the log that the inj DC appears to be dropping away.

Is there something I have missed when scaling the injectors which is causing some sort of torque limit?

[Alvin]

There is a 255kpa limit on these OS's. When you hit 255kpa of boost you have a hard shut down.

Perhaps the same limit exist at 230kpa when the VE table only goes to 230kpa. You can change that axis to go up to 255kpa

[Cringer]

There is a 255kpa limit on these OS's. When you hit 255kpa of boost you have a hard shut down.

Perhaps the same limit exist at 230kpa when the VE table only goes to 230kpa. You can change that axis to go up to 255kpa

Looks like he is around 100-118 kPa of boost according to the log. Using an XDF Verlon developed I see this OS is capped at 50 kPa of boost. However, I am reluctant to modify the tune because the OS ID's are different and the XDF was developed for an E38, so it is possible the XDF does not apply. The max boost of the E38 is zero since it was intended for N/A applications. I would expect the E67 to be greater than zero due to its target applications for boost.

There is a safety airmass calculation limit for dynamic airflow. It is calculated as VE at max reachable MAP which is Baro + MaxBoostTable.
MaxBoostTable is zeroed on all NA engines and I've filled this table with 80kPa.
You won't see it in HPT comparison.
If exceeded, airmass will be clamped, engine will go lean with a higher spark.

https://forum.hptuners.com/showthrea...l=1#post806863

Here is the screenshot we can see those symptoms. CylAirmass goes flat. Timing is advanced. And it goes so lean that even the narrow band O2 voltage dips.

max boost exceeded.jpg

[Alvin]

I saw around 230kpa towards the end of the log. His 2 bar VE table stops at 230 kpa. The first thing I'd do is move that to 255 and see if it fixes it. The hard shut down is exactly what I see when I try to take that OS past 255kpa of manifold pressure.

[Cringer]

I saw around 230kpa towards the end of the log. His 2 bar VE table stops at 230 kpa. The first thing I'd do is move that to 255 and see if it fixes it. The hard shut down is exactly what I see when I try to take that OS past 255kpa of manifold pressure.

Definitely sounds like a logical first step.

[abc]

I see it making it to 254 kpa. Looks like the MAP limit Alvin is talking about? Can you scale the airflow down?
254.png

[Cringer]

2.5 Bar MAP - Speed Density (E38/E67 ECM)

• Features:
  
  • 2.5-bar MAP sensor support (255 kPa).
  • Rescales High MAF table (up to 15,400 Hz and 1024 g/sec airflow).
  • Adds new VE tables (33x33 resolution with configurable MAP and RPM axes).
  • Adds TPS-based VE multiplier table (33x17 cells).
  • Supports both MAF and Speed Density mode.
  • Adds Boost Enrich tables and fuel cut based on MAP thresholds.
  • Rescales fan temperature axis (163–250?F, 73–121?C).

https://support.hptuners.com/support...r-differences-

[Lightning Performance]

I saw around 230kpa towards the end of the log. His 2 bar VE table stops at 230 kpa. The first thing I'd do is move that to 255 and see if it fixes it. The hard shut down is exactly what I see when I try to take that OS past 255kpa of manifold pressure.

I will adjust the VE table this morning and give it another shot. Although the boost only seems to be peaking at 230-250KPA when this "cut" is happening. The MAP appear to be fairly stable at 210-218 KPA throughout the run. It is unusual that I can see a knock event in the scanner then my CYL AIRMASS goes up and then my timing goes up as well... I can't figure out where the advance is coming from either...

[Cringer]

I will adjust the VE table this morning and give it another shot. Although the boost only seems to be peaking at 230-250KPA when this "cut" is happening. The MAP appear to be fairly stable at 210-218 KPA throughout the run. It is unusual that I can see a knock event in the scanner then my CYL AIRMASS goes up and then my timing goes up as well... I can't figure out where the advance is coming from either...

See my first response in this thread.

[Lightning Performance]

See my first response in this thread.

Yes Cringer, I agree it does appear to be a similar problem. I think you are right about the E38/E67 boost limits as this is a factory supercharger vehicle.
See the log attached from last week when I started to dyno the vehicle, it pulls cleanly through to 6100 with no issues besides the vehicle starting to go lean due to the injectors being too small.
This issues seems to only have occurred since I fitted the larger injectors and scaled the tune...I suspect there may be other tables I also need to rescale (others than I have already) that is causing some sort of clip.
Injector maxed out.hplOld tune 90lb Deatschwers injectors.hpt

[blindsquirrel]

since I fitted the larger injectors and scaled the tune

Scaled as in just Stoich/IFR/AFR Term scaling to make the injectors fit the 127lb limit, or airflow scaling where every damn thing in the world has to be changed?

edit: And datasheet that came with the injectors is...?

[blindsquirrel]

Why is Dynamic disable/reenable so high with MAF not failed?

[Lightning Performance]

Scaled as in just Stoich/IFR/AFR Term scaling to make the injectors fit the 127lb limit, or airflow scaling where every damn thing in the world has to be changed?

edit: And datasheet that came with the injectors is...?

Correct only basic Stoich/IFR/AFR Term.

Injector data sheet attached.

[Lightning Performance]

Why is Dynamic disable/reenable so high with MAF not failed?

Blindsquirrel, The vehicle was previously tuned at another shop. The dynamic & MAF fail settings are something I have overlooked. The MAF signal wire is physically disconnected.

[Hondaeater]

Log Ethanol fuel % channel. Looks about 50% Yes?

Did you 1/2 the injector data using Excess 1500cc injectors ?? = unscaled starting with 93.6lb/hr to 229lb/hr at the far end of IFR.

Your Dynamic flo at idle is 2.62 lb/min. Injector data is suspect.

[Lightning Performance]

Log Ethanol fuel % channel. Looks about 50% Yes?

Did you 1/2 the injector data using Excess 1500cc injectors ?? = unscaled starting with 93.6lb/hr to 229lb/hr at the far end of IFR.

Your Dynamic flo at idle is 2.62 lb/min. Injector data is suspect.

Fuel should be straight E85 I filled it last week, vehicle has only been run on straight E85 for the last year or so, although haven't tested it.
Yes halved the IFR and doubled the stoich values.

[L1FTD]

Yes Cringer, I agree it does appear to be a similar problem. I think you are right about the E38/E67 boost limits as this is a factory supercharger vehicle.
See the log attached from last week when I started to dyno the vehicle, it pulls cleanly through to 6100 with no issues besides the vehicle starting to go lean due to the injectors being too small.
This issues seems to only have occurred since I fitted the larger injectors and scaled the tune...I suspect there may be other tables I also need to rescale (others than I have already) that is causing some sort of clip.
Injector maxed out.hplOld tune 90lb Deatschwers injectors.hpt

Here's a few small changes to boost limits and Dynamic Air. Same as what Cringer stated, and has come from the Legend Verlon. Your car and mine have the same OS. May not fix your problem though.

Might need to licence the FPCM too, couldn't see that in the tune. Or try setting 'FPCM Fitted' to NO, it will run off Default pressure and not follow the factory flow rate switching.

Also try making all your VE tables the same. Set them all to the Open. It does drop off a cliff after 181.5kPa though..

Stock MaxBoost.png Adjusted MaxBoost.png

LSA RPM Cut + Boost&DynAir.hpt

[Lightning Performance]

Here's a few small changes to boost limits and Dynamic Air. Same as what Cringer stated, and has come from the Legend Verlon. Your car and mine have the same OS. May not fix your problem though.

Might need to licence the FPCM too, couldn't see that in the tune. Or try setting 'FPCM Fitted' to NO, it will run off Default pressure and not follow the factory flow rate switching.

Also try making all your VE tables the same. Set them all to the Open. It does drop off a cliff after 181.5kPa though..

Stock MaxBoost.png Adjusted MaxBoost.png

LSA RPM Cut + Boost&DynAir.hpt

Ran the vehicle just then with your updated file, got 3 good pulls out of it before it went into cut mode again.
Updated the file with the suggestions Blindsqurrel had and got another good run then failed again.

I have noticed the injector b1 & b2 m/s are showing a discrepancy when the issue is happening...

See logs attached.

[L1FTD]

Ran the vehicle just then with your updated file, got 3 good pulls out of it before it went into cut mode again.
Updated the file with the suggestions Blindsqurrel had and got another good run then failed again.

I have noticed the injector b1 & b2 m/s are showing a discrepancy when the issue is happening...

See logs attached.

Here's another to try, minor changes, might not do it. FPCM set to NO and all VE tables match.

Can you log another fuel pressure PID? I can only see the commanded and estimated. The fuel pressure estimated is dropping real low and shooting up at times, seems to correlate with when you get the issue.

Is there still an FPCM in the car? Can see you're using aftermarket pump setup. There are more settings in the FPCM, don't know if you've licensed, couldn't see it in your tune.

You could try a run in full open loop, disable the o2's. Clear out the fuel trims in scanner. Make sure it's not carrying over a positive fuel trim affecting one bank of injectors.

LSA RPM Cut + Boost&DynAir + FPCM&VEtables.hpt

[Lightning Performance]

Here's another to try, minor changes, might not do it. FPCM set to NO and all VE tables match.

Can you log another fuel pressure PID? I can only see the commanded and estimated. The fuel pressure estimated is dropping real low and shooting up at times, seems to correlate with when you get the issue.

Is there still an FPCM in the car? Can see you're using aftermarket pump setup. There are more settings in the FPCM, don't know if you've licensed, couldn't see it in your tune.

You could try a run in full open loop, disable the o2's. Clear out the fuel trims in scanner. Make sure it's not carrying over a positive fuel trim affecting one bank of injectors.

LSA RPM Cut + Boost&DynAir + FPCM&VEtables.hpt

I'm not sure I can log actual fuel pressure , I don't remember seeing the pid when I set those up...
FPCM is still fitted to the vehicle and is controlling a KPM 1500HP VE-VF pump module, carried out the fuel pressure table updates as per the kit instructions.

I have not licenced the FPCM as of yet.

It's a bit odd I've been playing around all afternoon, I tried going back to a file pre scaled injectors file, loaded current inj data and just run it at the max 127lb/h limit and just tuned around it - had no issues, besides the tune ending up all funky as you would expect.
Then I reloaded your first file back in and have had 2 successful runs. Seems rather inconsistent....