And how would one find or figure out what the "PS2 characteristics" are? I have a PS2 on my E82 N55, and while I'm using a JB4, I'm trying to tune the BEF in the areas the JB4 can't, like timing and AFRs. I'd love to be able to tune the BEF to the PS2 rather than the OEM turbo with a piggyback controlling it.
On E-series go Commanded Waste gate approach and get ready to spend a crap ton of time and money (tires, brakes, fuel, etc.). I started down full PID and then gave up and paid SBrach to provide me a tune. I still play around and learn, but have a fall back at the end of the day when I'm mentally exhausted from trying to understand what the DME is doing.
When I get time, I plan on branching the 980GB XDF and adding in all the new tables I ported over from other XDFs. It's sad how the XDF stopped getting updated about 3 years ago. We'll see if they accept my additions. If not, then I'll publish somewhere else.
Here is my latest attempt... Oh yeah, post shift boost spikes are the hardest part of self tuning. Mine just sort of works, but I couldn't tell you specifically how.