2015 F150 Ecoboost, can not get higher than stock boost

I worked with this truck for a while, and read all of the threads related to this issue (as it seems a couple people have it sorted, but a lot are having the same concern.) I tried two tunes, and tried them both on the dyno as well as the street. Surprisingly the tune that had the least amount of changes actually produced the most power. I will post both tunes, in hopes that someone can help me get past this limit of boost. It seems to me as something is missing in the tune file. The PCM has desired TIP, but I can find no table/chart that associates anything int he file with TIP. No airflow=tip no torque=tip nothing. There has to be something that the PCM is using to calculate a desired TIP.

That said I am using version 3.4 so maybe that is the issue.

The first tune which actually has very minor changes produced 355rwhp 395rwtq at 14psi boost and drove amazingly well and very responsive.
This tune is labeled CUSTOM2 The log file I attached is from this tune as well and is from the dyno. I noticed that some pulls it would hit "insuficient fuel" for torque airflow limit. I found that it would hit this on the stock tune as well. I never saw a drop in fuel pressure. No changes ever seems to consistently change it from randomly hitting this limit.

You have to raise your driver demand.
The PCM calculates desired TIP from a desired airflow, which comes from a desired torque.

All you've done is make the pedal translation more aggressive in your take2, but you have not raised your desired torque. You can raise your load limits all you want, but if you don't request more load, it wont happen.

Try bumping up your Driver Demand torque and going from there. Your other option is to mess with the Torque Model itself, but that has consequences most don't fully realize.

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Originally Posted by Bugasu

You have to raise your driver demand.
The PCM calculates desired TIP from a desired airflow, which comes from a desired torque.

All you've done is make the pedal translation more aggressive in your take2, but you have not raised your desired torque. You can raise your load limits all you want, but if you don't request more load, it wont happen.

Try bumping up your Driver Demand torque and going from there. Your other option is to mess with the Torque Model itself, but that has consequences most don't fully realize.

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Raising Driver Demand had no effect on boost at all. I tried drastic changes, and moderate changes. No effect. In the first tune file (just labeled "custom" you will see the DD tables were raised. That tune actually produced less power than the one with stock DD tables. May have been a fluke, but regardless it did not produce any more boost pressure.

I have a few more things to try and will go back on the dyno in a few days hopefully.

In my experience the wastegate and des. canister pressure feed fwd tables only allow for so much boost in the stock form. You will have to log these tables and see where your'e hitting the cells at and adjust either one or the other. I chose to adjust the wastegate duty cycle tables. To adjust boost for the des. canister pressure feed fwd tables go up in numbers to lower boost and go down in numbers to raise boost. About 1 in these tables is about a lb in boost. In the wastegate duty cycle tables go up in numbers to raise boost and down in numbers to lower boost. About .100 in these is around a lb in boost.

Thank you 02reaper. Ill look at those functions

I still feel that something is missing in these files. The PCM has a desired TIP. There has to be a table for the PCM to calculate what desired TIP is. IE Desired torque=x TIP or Desired airflow = X TIP. The PCM needs some mathematical basis to calculated what desired TIP would be based on the torque/airflow or load that it wants to see, and I have found nothing in any of the tables that relates the two.

Maybe Eric can chime in and look to see if they're any missing tables that he can add to assist us.

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Originally Posted by 02reaper

Maybe Eric can chime in and look to see if they're any missing tables that he can add to assist us.

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It could be me too, as I am running 3.4. Support has not replied to my email for 3.5

Eco is interesting and complex on how it derives it's desired TIP calculation. All the tools are there in 3.4 to raise it. I have successfully tuned a few trucks with it on 19-21 psi give/take. However, it's a little bit of a learning curve for sure! Best advice, there are threads here that were a big help to me in the beginning as well, it's a lot of reading/understanding, but in the end you will get what you need from them for more boost.

Looking at your logged PIDS, it appears when you load the motor, your "driver demand limit source" change to "combustion stability". Looking at your tune, Engine>Torque Management>General>Combustion Stability Limit is set at 203.2kPA, which the PCM does a nice job of holding it at during your pull. This should go up to 220 kPA or so depending upon MCT increases. Once that is corrected, you will likely have to increase "Driver Demand Engine Torque up as well.