Torque Control Issues - Supercharged '16 GT

[JFiorito]

Hey guys,

I'm having some driveability issues. Specifically at low RPM and low load my timing jumps all over the place as my Spark Source repeatedly jumps between Base and Torque Control:

InkedDriveability Issues_LI.jpg

Does this mean my ETC Torque Request and/or Scheduled torque for these conditions is exceeding my Driver Demand tables? I have tried increasing the Driver Demand tables and that didn't seem to do the trick. I've also tried raising and lowering my Torque Tables for the given mapped points (and adjusting inverse tables), and I've adjusting my MAF Airflow vs Period.

Setup is '16 GT (M/T) with 2.3L Roush blower, 72mm upper pulley, 1050cc injectors, 1 7/8 long tubes (w/ cats), 2 7/8" cat-back


I've attached a log with a cold start, cruise, and some high load conditions. Matching tune as well.

TTS V3 - increased MAF period table 3.30.20.hpt
TTS V3 Drive 1 3.31.20.hpl

Any help would be appreciated

[small tuner]

i will start by disable LT fuel trim and fix short term errors and make sure these are correct value (Predicted Throttle Angle & ETC Effective Area) along with torque/inverse tables . is it return or returnless fuel system. what strategy you are using..roush ?

[JFiorito]

i will start by disable LT fuel trim and fix short term errors and make sure these are correct value (Predicted Throttle Angle & ETC Effective Area) along with torque/inverse tables . is it return or returnless fuel system. what strategy you are using..roush ?

I think my Predicted Throttle Angle and ETC Effective Area are pretty accurate. I don't think those have been changed since the original Roush tune:

ETC Angle Error.PNG
ETC Torque error.PNG

Am I mistaken there? (ignore the red cell, it died on first startup)

I am still on the stock returnless fuel system with the voltage booster that came with the Roush kit. I think I am still running the Roush strategy, I still don't fully understand the different strategies...

[small tuner]

I am still on the stock returnless fuel system with the voltage booster that came with the Roush kit. I think I am still running the Roush strategy, I still don't fully understand the different strategies...

then correct injectors data. you are using return values on returnless fuel system

[JFiorito]

then correct injectors data. you are using return values on returnless fuel system

Forgive my ignorance, but where do you see this?

[small tuner]

inj tvs.PNG

[JFiorito]

Ah thank you. I had no idea that meant all 1's meant a return style fuel system. I will return it to the Roush values and see what happens.

Thanks

[blackbolt22]

Ah thank you. I had no idea that meant all 1's meant a return style fuel system. I will return it to the Roush values and see what happens.

Thanks

Why was it changed in the first place? Did someone else tune the car or you? People change all sorts of settings that don't ever need to be touched. Less is more.

[JFiorito]

Why was it changed in the first place? Did someone else tune the car or you? People change all sorts of settings that don't ever need to be touched. Less is more.

Yeah that must've been changed when it was tuned on the dyno. I remember him struggling to get it to respond how he thought it should. Ended up running alright at OP, but a lot of other things were acting funny after that. Made 620 whp (was 95 degrees and high humidity). I thought it should've put a little more down, but I could just be optimistic.

I changed that back to Roush's values and turned off LTFT. My STFT were pretty far negative. I just made a new tune so hopefully I made the right changes. Maybe you guys can advise. I have a histogram of STFT vs MAF period, so I took those values and changed by existing MAF Airflow vs Period by that amount (i.e. if the STFT was -0.10, I multiplied by existing Airflow value by 0.9). So my MAF Airflow vs Period is now lower for most of the entries.

STFT.PNG

[JFiorito]

Still having issues with Torque Control. I have progressively changed my Torque tables up and down in increments of 10lb-ft for the problem areas and that hasn't made a difference. Next I've moved on to adjusting the Driver Demand tables in a similar fashion, but still no noticeable changes. Next I moved on to adjusting my timing in those problem areas. I lowered everything around 8 degrees (55 to 47) This has made it behave differently... Still not correct though. I have a bit more consistency in steady state cruising, but occasionally it does flutter in and out of Torque Control. The swings in timing seem to be more extreme now, but less often. It also seems to be way worse before everything is up to temperature.

Attachment 98706

Attachment 98707

Can anybody provide any insight as to what triggers Torque Control to kick in? From what I've read it sounds like your torque tables exceeding the driver demand tables, but adjusting those doesn't seem to make a difference. Also, what controls the timing while it is in Torque Control mode?

[CCS86]

Still having issues with Torque Control. I have progressively changed my Torque tables up and down in increments of 10lb-ft for the problem areas and that hasn't made a difference. Next I've moved on to adjusting the Driver Demand tables in a similar fashion, but still no noticeable changes. Next I moved on to adjusting my timing in those problem areas. I lowered everything around 8 degrees (55 to 47) This has made it behave differently... Still not correct though. I have a bit more consistency in steady state cruising, but occasionally it does flutter in and out of Torque Control. The swings in timing seem to be more extreme now, but less often. It also seems to be way worse before everything is up to temperature.

Attachment 98706

Attachment 98707

Can anybody provide any insight as to what triggers Torque Control to kick in? From what I've read it sounds like your torque tables exceeding the driver demand tables, but adjusting those doesn't seem to make a difference. Also, what controls the timing while it is in Torque Control mode?

Log and compare "desired MAF" to actual MAF. If your MAF transfer function, ETC tables, or TQ/inverse tables have errors, the engine can ingest more air than it wants, and use spark to cut torque.

[JFiorito]

Log and compare "desired MAF" to actual MAF. If your MAF transfer function, ETC tables, or TQ/inverse tables have errors, the engine can ingest more air than it wants, and use spark to cut torque.

Never saw this channel before. Just added it and will record some logs. My ETC Angle Error and ETC TRQ Errors are really small. I have about +/- 0.2 angle error and about <= 0.5 TRQ error. My TRQ tables were not adjusted after I went to a smaller pulley, however none of the changes I've made there seem to do much. Unless I am making too small of adjustments. Where can I find the MAF transfer function and what does it do?

[JFiorito]

Never saw this channel before. Just added it and will record some logs. My ETC Angle Error and ETC TRQ Errors are really small. I have about +/- 0.2 angle error and about <= 0.5 TRQ error. My TRQ tables were not adjusted after I went to a smaller pulley, however none of the changes I've made there seem to do much. Unless I am making too small of adjustments. Where can I find the MAF transfer function and what does it do?

Is the MAF transfer just MAF Airflow vs Period?

[rryanfla]

Yes airflow vs period or voltage

[JFiorito]

Alright so I started logging my MAF vs Desired MAF and it definitely varies quite a bit in certain areas. So my question is, how do the TRQ/Inverse tables affect the MAF? I lowered my TRQ tables by 20% in these low load areas and things got really whacky. I think I am going to raise them by 20% next and see how that goes.

Also in terms of MAF tuning, I have been making a histogram of my STFT's and then adjusting the MAF Airflow vs Period based on those. I can get my STFT's pretty small (under 3%) but that seems to screw up my LTFT's which doesn't make sense to me

[JFiorito]

Also, where do the Driver Demand Tables come in to the equation? I feel like those should have been adjusted when I went to the smalley pulley, but they are the same

[Relentless]

So my question is, how do the TRQ/Inverse tables affect the MAF? I lowered my TRQ tables by 20% in these low load areas and things got really whacky. I think I am going to raise them by 20% next and see how that goes.

so the Tq tables are based off Load and RPM. Load is going to go up with more boost. An N/A motor will have a peak load of around ~100% load, and a boosted motor will double load every 14.7 PSI. So what you can do if you are seeing load's over your torque tables max load you can re-normalize the table to match what you are seeing. I would start by multiplying the % of load changed. say your old max is 1.00 and you are making 400 ft/lbs TQ then at 1.50 load i would start with 600 ft/lbs. Your motor references these torque tables to reference how much air and fuel the motor will need. You can dial your torque in after that based on your logs.

Also after doing anything to your torque calculations doing forget to calculate your inverse tables. edit>torque inverse calculator.

Also, where do the Driver Demand Tables come in to the equation? I feel like those should have been adjusted when I went to the smalley pulley, but they are the same

Driver demand is just that. You are no longer pushing a pedal that opens a throttle body causing the engine to make more power. Now you are pushing the pedal that looks at the driver demand table say 50% pedal 5000 RPM and what is in that box (say 350 ft/lbs) is what it references for its torque request. There are many things i am leaving out to what it actually requests, but this should paint the picture. this sounds more confusing (which it is) but it allows the driver to have more accurate control of the power and it allows the motor a way to cut power when it needs to. i.e. rev limit, traction control and so on.

I hope this is helpful. Good luck.

[JFiorito]

Thank you that was a good explanation, but I have a few more questions for you. For starters, which torque would you reference to adjust your TRQ tables? Scheduled TRQ? I went from a 79mm upper pulley to a 72mm, so I think the boost was supposed to increase by 1-2 psi and therefore load would increase by roughly 10%, right? This all makes sense, but my changes don't seem to be doing what I think they should... I just increased my TRQ tables (and then adjusted their inverses) by 3 lbft and now it won't even hold an idle anymore...

TRQ 3 ftlb.PNG

It seems like it's trying to hold 30* of spark at idle while before it was only 13*. I've increased these points and decreased them by 3 and 5 ft-lbs. When I increase them it throws a ton of spark and dies out. If I decrease them then it has about 0 spark and dies out.

Next I am going to try to increase my Driver Demand tables. This is basically my torque request right? If I request more torque at these areas then it should not have to flip into Torque Control mode anymore? Or should I try and increase my Maximum Torque 2A, 3A, and B?

Max TRQ.PNGMax TRQ.PNG

[Relentless]

Next I am going to try to increase my Driver Demand tables. This is basically my torque request right? If I request more torque at these areas then it should not have to flip into Torque Control mode anymore? Or should I try and increase my Maximum Torque 2A, 3A, and B?

Max TRQ.PNGMax TRQ.PNG

Your Driver demand tables are under Torque Management>Driver Demand, then if you are manual there is a table for each gear and one for launch.

[JFiorito]

Hopefully we're on to something as I have no issues in 6th gear. I increased my Driver Demand tables by 10ft-lb at the lower pedal/RPM areas. Will report back tomorrow