Max Demanded Throttle Voltage (44389)

Looking through my tune some more .... I see this table within AIRFLOW. Searching the forum for details about it makes me think that either it is not being used for my OS, or HPT got the mapping wrong, or I just don't understand what it's used for.

It seems this is used to set a limit by RPM, for the throttle WOT limit ... but factory values for my tune are all very small and the scale looks strange:

Attachment 152755


Here's the same table from a 2021 Durango Hellcat and a 2024 TRX (both have the same values in this table):

Attachment 152756


Every other tune I look at has this table scaled from 0 - 5v like the HC/TRX I posted above, but my factory calibrations have it from 0 - 0.3v with some odd scaling??

Does this warrant a ticket into HP Tuners, or should I just go ahead and change it? If they have it mapped incorrectly, I'm just concerned with what I would actually be changing if I tried it ...

look at a early scat compared to a 1320 in the clutch pressures...

same sort of thing:

I ended up submitting a ticket for this on Friday, but haven't heard back yet. Hopefully hear back soon.

I really seems like they've mis-mapped this table in my OS

my point was that here and there the factory does all sorts of stuff like that in the axis's

its like those weird single values that they just randomly toss into a table

those do not make sense either

which is why i leave them alone

Gotcha. It actually makes sense to me in some way, but I deal with data modeling quite a bit.

When you have limited fields available, and a system which interpolates .... you can throw values into the model which are outside any realm of what you'll see in live data, just to serve as a data point to give you the resulting curve you're after .... which the interpolation will then use in processing live data.

The axes definitely looks weird in 44389, but my bigger concern are the cell values being so small. This couldn't really be the Max Demanded Throttle, as if it were, I would have a very dead pedal I think .... Or my OS doesn't use this table in the way I think it does?

HP Tuners responded earlier this morning and said they are escalating it to engineering.

Quote:

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Originally Posted by Stoopalini

Gotcha. It actually makes sense to me in some way, but I deal with data modeling quite a bit.

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oh good

please explain this table:

*just the when you are currently in 8th gear part thx : )

That table is not representing modeled data or leveraging any interpolation, it's just singular data points ... sorry, can't help with that one :confused:

Just don't down shift from 8th to 4th I guess??

Quote:

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Originally Posted by Stoopalini

Every other tune I look at has this table scaled from 0 - 5v like the HC/TRX I posted above, but my factory calibrations have it from 0 - 0.3v with some odd scaling??

Does this warrant a ticket into HP Tuners, or should I just go ahead and change it? If they have it mapped incorrectly, I'm just concerned with what I would actually be changing if I tried it ...

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That is either scaled incorrectly or completely mislabeled on your platform.
Support ticket definitely warranted.

Was this read using the latest stable VCM version or the latest Beta version?

Quote:

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Originally Posted by HaasExp

That is either scaled incorrectly or completely mislabeled on your platform.
Support ticket definitely warranted.

Was this read using the latest stable VCM version or the latest Beta version?

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It’s with beta as the latest stable version doesn’t support my OS at all. I couldn't even do a read with the stable version.

As I wait for HP Tuners support, I'm looking a bit deeper to see if I can figure out why these values would be what they are without making my accelerator pedal feel dead ... assuming the table is mapped correctly that is...?

Here is a look at my OEM calibrations

Attachment 152915


It appears Pedal Follower Enable % is set to 100% across the board. I was thinking maybe this negates the Max Demanded Throttle Voltage table from being referenced, but the description for this table states: "[ECM] 35862 - Pedal Follower % Torque Threshold: Pedal Follower transient mode will enable if torque percentage is greater than this"

If that is correct, then I think it would result in PF mode never being used since torque would never be above 100%, right?


Here are what these tables look like on a 2021 Durango Hellcat (same as a 2024 TRX):

Attachment 152916


This looks like the WOT Override and Max Demanded throttle are set in such a way to manage the WOT throughout pedal travel and RPM range, but the PF % would essentially be the same as mine since it has 200% entered into the 801 RPM field, which is the top of the map. So anything off idle would have 200% torque as the threshold to enable PF Mode.

No answers here, or even any more clarity ... but I'll keep trying to understand this better....

add the pics as attachments

like you would a tune

can really see them with the "insert image" feature

Quote:

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Originally Posted by LilSick

add the pics as attachments

like you would a tune

can really see them with the "insert image" feature

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If you tap (or click) on the thumbnail, it'll open full screen ... does it not do that for you?

I just checked and they are listed as attachments. I just inserted them "in line" on my post.

If you tap or click the image, it should open just like an attachment which isn't inserted "in line"

it does but its blurry

if i then right click on the blurry image i can then select to add a new tab and if i click on that tab the image will be clear there

its a glitch

i thought you had stated that with the smooth boost controller you were happy with your throttle?

what changed?

what are you trying to make the throttle do?

or stop doing...

The Smoothboost is great! I cannot tell when the engine comes in and out of boost at all, it is very seamless with the Smoothboost and the way I have the TB Airflow Model table and Small + Large range tables setup. There is still a very slight hesitation at tip in, I mean milliseconds here, which I can probably dial out with some finer adjustments.

I would say the level of part throttle sensitivity and off-the-line torque can probably be improved, but before I experiment with different adjustments, I 1st want to gain a better understanding of how it all works together and what the available controls consist of.

In other words, I want to understand it better to be able to experiment with different adjustments to potentially improve on things.

For example, if I turn track mode on, and then disable all stabilitrac + traction control systems ... and floor it from a stop ... the power comes on a bit slowly. It does take off, but there's no wheel spin associated with it. In studying the different tables and reading posts on here, it seems that dialing in tables 44389 and 35740 can give you some pretty precise control over the WOT delivery when pushing the accelerator pedal to the floor from a stop, but of course, when I looked at 44389, it doesn't make sense ... So I want to better understand this before I try adjusting it.

When in track mode (see attached PDF for drive mode supplemental), torque vectoring directs 70% to the rear and 30% to the front ... so with traction control and stabilitrac completely disabled, I would expect the tires to break lose if I punch it from a stop. I know there is still work to be done on the fueling and on the spark, but I wanted to dig into the throttle as well to understand if there's opportunity there as well.

So I just heard back from HP Tuners, and this was their reply:

Quote:

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Originally Posted by HP Tuners Support

Hello,
Thank you for contacting HPT Support.

The issue has been fixed in the latest BETA software version and the engineer also 138 tables added to the definition.

Please, update your software to the latest BETA version :
https://files.hptuners.com/VCM%20Sui...e%20(Beta).msi

Resync your Interface after the update has been done and you should be good to go!

Good luck.

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So I updated to the latest Beta and then opened the original read of my PCM, but nothing looks different. I am now doing a full read of the PCM and TCM, to see if reading it back out with the latest Beta will have it looking different.

Hopefully doing a fresh read now will have things looking correct ... unless, when I did the writing back to the PCM with the mismapped tables, it messed them up. So those tables now have incorrect values stored in the PCM due to the VCM mapping issue.

If that's the case, I asked HP Tuners if they could retrieve my OEM calibrations from their files (since they unlocked my OEM PCM back in July) and send to me. Maybe that will get me a clean slate to start from?

they only added 138 tables???

you got burnt : )

LOL ... Hopefully it resolves the strange airflow behavior I've been having to work around ... maybe I can undo the Control Goal FAR target adjustments I had to make to get the fueling into a safe range during the transition from vacuum to boost?

So I updated VCM, resynced my interface, and did a fresh "Read Entire" of the PCM, but everything still looks the same. The values in 44389 haven't changed, so I'm assuming they are accurate representation of what is in that table, or ... The mismapped configuration has caused bad values to be written back to the PCM through my numerous writes. Hopefully HP Tuners has a copy of my untouched calibrations from when they unlocked the PCM.

That said, I'm not really sure what it means when engineering has added 138 tables to the definition. I definitely don't see any new tables in VCM Editor, so does this mean there were tables reflected in editor which just weren't mapped to the PCM? So when I was doing write activities, any changes to these tables were not being written to the PCM? I did a compare of the new read file to my previous tun file, and it doesn't show any differences.

If it is the case that some tables shown in VCM editor just weren't mapped to the PCM, but now are .... then I wonder what will happen the 1st time I write and these 138 tables and values now get written where previously they weren't?

Or maybe I am misunderstanding what "engineer also 138 tables added to the definition" means...

So this morning, I noticed there was yet another Beta version update ... so I downloaded and installed it.

Now, the table shows reasonable values in the cells but the axes still looks wrong.

Attachment 152971

Wow wait

You’re saying that using an updated version of scanner that the values in the table changed???

Quote:

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Originally Posted by LilSick

Wow wait

You’re saying that using an updated version of scanner that the values in the table changed???

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Not scanner, but editor.

Using an updated version of VCM Editor, the values now look correct ... yes, although the axes still look wrong. I've sent another message in asking about it, so we'll see.

I have been pretty confident this whole time they had some mappings wrong, and now I wonder how many other tables may have had similar mapping issues. I've been combing through the calibration file, trying to see if I can identify any other areas ... but I can't do a compare of course, since you can't compare files across different versions of VCM Editor.

I may install the older beta on a separate computer and do a tab-by-tab comparison to see what (if any) other areas may also be impacted.

Of course I meant editor - smoked

Every once in a while my mouth waits for my brain : )

I use Windows 10 a bootleg version with absolutely no One Drive cloud nonsense and can compare across editor

Scanner is different and sometimes I need to back up for a log to load


Updating The VCM suite should not change any of your tables

Well, it did change the values. I even loaded the old beta on a different computer and loaded the same tune file to compare. The values in this table are definitely different between the previous beta versions and the latest.

All my computers are Windows 10 (not bootleg) with no one-drive on any of them.

The values changed because they had the translation mapping wrong.

I also now have access to Barometric Pressure characterization fields on the AIRFLOW tab, which I didn't have before.

Also have a few other things available too ... Haven't had time to dig through it all or try a new load or log yet, but hope to tonight.

Quote:

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Originally Posted by Stoopalini

Now, the table shows reasonable values in the cells but the axes still looks wrong.

Attachment 152971

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That looks fine to me. Now to check if it actually works.

Quote:

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Originally Posted by HaasExp

That looks fine to me. Now to check if it actually works.

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Yep, agreed.

A recent log does show throttle voltage ramping with RPM when pedal voltage is constant.

Attachment 153005

This picture also shows (what I think is) torque mgt pulling throttle during shifts when not at WOT, but I'll start another thread related to that topic.

just on that table pot all the values on 4.0000 but leave the first one