2.3 Ecoboost weird load behavior

[jamesm]

Hey guys.. just wanted to throw this up here to illustrate an issue i've been seeing tuning my 2.3 Focus RS. This rom was created/logged specifically to show the issue as clear as possible, and I'll try to break it down as best as I can.

Basically, even with no visibly active limiter and actual load < desired load, boost below the maximum etc it's still shutting the throttle and preventing load targets from being reached. It's almost as though there is some airflow limit or something that I just can't see. This issue is intermittent, it seems. Sometimes it'll spike boost (that's what i'm trying to fix) then quick bring the load right in line and hold exactly what i ask.. other time is just hangs out around 2.5g/rev with the throttle mostly shut. I'm at a bit of a loss with this whole 'correcting for overboost from a catless downpipe' thing, as nothing seems to really do what you'd expect and it's not very straightforward :/.

Anyway, log and rom is attached. Maybe someone will see something I missed. Thanks in advance.

load-issue.hpl
HRI-base.v70.hpt

[Bugasu]

From what I can see, TIP Actual > TIP Desired. As such the throttle must close off to control airflow that would be more than it expects.
As to what is capping your TIP Desired, based on the values, your Compressor Outlet Pressure limit is very close, and after the ECU compensates for the pressure drop, I think it lines up pretty much dead on.

As to the catless downpipe changes, you're changing the post turbine pressure. Correct for that in the ECU so the model is correct again, and you'll find everything else magically fixes itself.

[reubone]

As to the catless downpipe changes, you're changing the post turbine pressure. Correct for that in the ECU so the model is correct again, and you'll find everything else magically fixes itself.

is there a thread with a solution or math that can shed some light on how to shift the torque model?

[jamesm]

Compressor outlet limit was it... i wasn't accounting for pressure drop.

As for the boost.. that's a tricky one to get right. Still trying to figure out exactly what needs to change, but it's coming along. Thanks for everything.