Ignorant question pertaining to load, TQ Based Decel while acclerating

[murfie]

Its been years since I played with these tables, so I went out and retested this to refresh my memory, its the Aircharge mult tables for calculated load. They need to be adjusted along with the load at WOT table if you want desired load to not be limited. veeefour is right the maximum load tables don't seem to do anything. I've just told people to modify both because its been so long I forgot which was which.

Heres a stock pull vs the only change being the maximum load tables set to .65. Zero difference between the two.

Stock vs .65 max calculated load list.jpg

Desired load is governed by calculated load via IPC. This is what happens when you set aircharge multi to .65. airload and desired load follow each other as normal below the new limit. Calculated load (based on throttle airflow) raises much faster than throttle angle (based on DD table torque values). Once the ECU figures out they don't just disagree, but the airflow is much higher than the throttle angle in the TB model says it should be, you get a wrench light. Load breached .6 (.65 * the load at WOT aircharge), calculated load is at 100% and airflow was increasing. The stock system acted very quickly to a hardware problem. Desired load and all the torque based system is then set to FMEM bypassed and the pedal still uses calculated load to get its airload and engine torque values. You could just disable all the IPC and increase the allowed torque errors, and that is what most people do to stop wrench lights, well before the Whipple and Roush files were decrypted. This is just to show calculated load (the thing most people ignore) is the IPC and more trusted. The math equations modeling the physical hardware and MAP are more trusted than the air sensors or the position sensors which the desired load and TQ rely on. You should make sure these models are accurate before you just dump a bunch of error into the TQ-load tables. They are ment to take up some of the error the models inherently have, but not a whole lot like adding more than double atmospheric pressure does to the SD section and hence TB model and injectors flow model. Next to the MAF transfer, SD is the second most important model in the whole system. You can only correctly tune it with good MAF transfer, injector data, TB model, and a MAP sensor.

Line is where it light the wrench light

Aircharge mult .65 wrench.png

Operation with out the desired load/ desired torque. .65 aircharge multipler limits to .6 air load fine and still reports accurate engine brake torque. Does not drive smoothly, especially at low throttle angles, where the TB model is not accurate and the load/ torque model is better.

Operating with out desired load.png

[engineermike]

Murfie are you saying desired load and torque can be limited by the ipc torque table?

[veeefour]

Why do you plp care about IPC at all? This just a sanity check that should be adressed at the very end or not at all..

[engineermike]

I think we agree that max map over BP can limit driver demand. But his max map over BP has been raised.

I think we agree that load at WOT can limit driver demand. But his load at WOT has been raised.

The funny thing is that I've seen where both parameters above set to stock NA values actually did not limit driver demand. I believe this is OS dependent or there are hidden switches that make this true/not true.

The point is moot either way, because both were raised by the OP.

What he didn't raise is the IPC torque table, which still tops out at stock values. I don't know why these haven't been raised and tested yet.

[murfie]

Murfie are you saying desired load and torque can be limited by the ipc torque table?

No I'm saying, desired load its limited by calculated load. IPC is just a sanity check to make sure air load and desired load and all the rest of the actual airflow from both TB model and MAF/MAP sensor to desired torque feedback loops agree with each other. IPC max and min need to be above and below where all of these fall. The closer you get your feedback loops to tighter max and min on IPC can be.

Calculated load is 0-100 in all applications NA or FI.

Absolute load(air load) is 0-105 for NA and 0-150+ FI.

[murfie]

I think we agree that max map over BP can limit driver demand. But his max map over BP has been raised.

I think we agree that load at WOT can limit driver demand. But his load at WOT has been raised.

The funny thing is that I've seen where both parameters above set to stock NA values actually did not limit driver demand. I believe this is OS dependent or there are hidden switches that make this true/not true.

The point is moot either way, because both were raised by the OP.

What he didn't raise is the IPC torque table, which still tops out at stock values. I don't know why these haven't been raised and tested yet.

OP did not raise either of the tables im suggesting. So unless this is a custom OS from roush or whipple they should.

Aircharge M and OP load problems.png

[murfie]

Sport modes pedal characteristics doesn't help trying to get your pedal and throttle to agree either.

[Pistol_91]

When I was trying to match my desired air load with actual air load a few months back, changing my inverse table in that certain mapped points and changing my SD tables via the calculator in that certain mapped points fixed every issue I had....

[engineermike]

OP did not raise either of the tables im suggesting. So unless this is a custom OS from roush or whipple they should.

Based on all the discussion so far, my best guess the WOT load parameter is what's holding back his DD. I think putting reasonable values there should be the next test.

I asked about IPC limiting torque demand based on your following statement, "Desired load is governed by calculated load via IPC" since desired load is a function of desired torque. Maybe I misunderstood.

I'd go ahead and fix the IPC torque tables anyway, if it were mine.

[veeefour]

Ideally desired load should be set high as you wont change tunes if you have a turbo with boost controller.
You want to run 7psi daily for example, but hit 27psi once in a while and not changing the tune every single time.

Now, desired load max value is a simple number located in torque model axis - there no calculation here and SD has nothing to do with that.
Now if you request 3.0 for example it will only set 3 at the beginning and will decrease gradually to match your actual load.
Like IPC this is just a sanity check - period.

[murfie]

"when I do a part throttle pull I am getting "TQ Based Decel" as the torque source."


This is not a tune issue, but a scanner polling speed issue. Trans shift mod also pops up for a while. There's really no good way in the scanner to see how fast these state and flag PIDs are updating except exporting to a CSV file that doesn't interpolate data gaps. For things like torque, load, or other numbered scalars that also may be updating very slow you can put it in a graph and set it to show count and view zoom data only. Zoom in to 1s and the number it shows is how many data points per second you are looking at. In this test run 3 log, torque source is only updating once every 2 seconds. A lot happens in 2 seconds, and that's not fast enough to be reliable information.

[Quicksand Jesus]

** UPDATE **

I want to thank everyone for their help. I have taken the following steps to "correct" the issue.

1) I set the MAP Max Delta above BP to 25
2) I set the MAP Map vs. Airmass to 49
3) I raised Load at WOT to 2.4
4) I left the Aircharge Mult for MP 14 at 1
5) I used the Torque Inverse Calculator to raise the TQ to almost double, then I was forced to "bend" it at lower RPM so the car would still idle properly
6) I moved the IPC min and max to "move it out of the way"

I appreciate all the commentary and enjoy trying to understand and learn new things. I'm constantly evolving, and what works on one strategy doesn't work on another. Now that I see that a significant change in load scaling and torque numbers in the inverse calculator changes the slope of load and makes a significant change on idle, I may open a new thread to investigate further.