mityaz

Hey guys,

I am trying to get a stable boost curve during a pull.
2011 GSR. Tephramod V3.
Rax patch enabled for "Atmos boost baro comp" and the Atmospheric boost set to 0.0 PSI.
Omni4bar is enabled.

The issue that i am having is that i keep getting negative WGDC correction even though i am under target. I want to maintain 25.1 PSI til redline. It almost seems that the ECU is targeting a different value than is in the Boost target table.
My understanding is that once "omni4bar boost" values dip under the target then my WGDC correction should go towards positive, but it stays -15. Please see the log. Time interval for WGDC correction is set to 1. It may be the case that my WG spring is pretty much running the show here, but still, i shouldn't see negative correction if i am under target.
Maybe my scaling is incorrect somewhere (but i tried to set the units to the ones that are listed in the XML code for each table). The baro value stays consistent in the logs.

Included is a pic of the rom tables and two logs. The other log is a WOT pull with WGDC table zeroed out completely (i included this for reference to see what it runs on WG spring pressure only)

Its an EFR 9174 .92A/R IWG turbo with a 26PSI Turbosmart actuator (preload set to 3.5mm).

THank you guys

mityaz

So i reduced the WG preload by about 4/6 of a turn and am now peaking just under 24PSI running WG spring pressure only.
I've adjusted my WGDC with all of the WGDC corrections zeroed out. I can maintain about 25PSI (+/- .5psi) all the way to redline. I then turned the corrections on and am still experiencing the issue.

So now, the correction starts out positive before the target is reached but after the target is reached, the correction stays positive and this is bringing my WGDC higher and is keeping my boost higher than the target is. It's almost like it's not updating fast enough (update interval set to 3ms) or some kind of hysteresis is going on where its not allowing the value to change.

Here is the pic of the current rom and a log to go with it.

Anyone?

mityaz

So i tried the RAX3 patch with the Smart EC enabled.

The results are still not what i expect them to be. The computer is adding WGDC and it is compiling and is driving my WGDC number up. All this happens while I am OVER target. I cannot make sense of this. It feels that i am missing something.

Attached is the current rom pic (with RAX3) and a log where you can see WGDCcorr just keeps stacking while OVER the target boost.

it almost appears that its trying to target the value in the "boost" column and not the "Omni_4bar psig" column. But my boost gauge on the dash is pretty consistent with the Omni4bar psig column. EDIT: i am referring to the columns in my log.

WickWhiteEvox

What mods do you have?

mityaz

well, here it is:

Its a built 2.4L with CNC 4pistons head, GSC S2, 9174 EFR turbo. (I updated my sig)

I dont think my mods are relevant to my issue tho. It seems to be "ECU" related.

mityaz

It appears that i have corrected the issue.

For anyone that may be reading this in the future:...

THe issue was that the values in the "Boost target" table were not exactly dialed in to the "WGDC table" so the ECU was trying to correct. The values were within 1-2psi. ALSO, and thats a big ALSO, the values in the "WGDC correction" table were too small to make much of an effect on the actual boost PSI so they ECU kept checking and correcting but there was no appreciable change in the actual boost, so it kept adding correction.

Fix: i set my target boost values a bit more precise to the values that the car would be running with the corrections turned off and i also increased the step interval in the WGDC correction table. So now, if i am over/under boost, each correction actually influences the WGDC enough to make a change in the boost level.

WickWhiteEvox

I usually change the max upward correction to 0 to dial in the boost, then allow it to adjust from there.
Also, since you're targeting 25 psi, check your map scaling

mityaz

What do you mean by map scaling? 3bar vs 4bar? If so, then yes, my 4bar patch is enabled in general and for atmospheric boost patch.