Not sure if you guys will find use for this or not, but I've been doing some testing on an E38 with a 2.5 bar OS. I asked support if they were able to build a 3 bar OS for my application, and it unfortunately won't happen.
Anyways, the issue I was having is that as soon as I'd push the OS beyond 24 pounds of boost (pegging 255 kPa) the ECM would get all pissed off and shut the throttle, kill the fuel, and the timing, then light everything back off like nothing ever happened. So finally I decided that I needed a way to limit what the ECM can see. In which case just by one kPa,
I played around with it for awhile and found a new calibration you can use to run an LS9 sensor and limit it at 254 kPa. This cured my issue, and even if I turn up the boost to 28 psi the ECM stops at 254 kPa, in which case my boost referenced fuel system takes care of additional fueling.
Linear: 254.00 kPa
Offset: 7.60 kPa
This is the new cal.
I figure that now if anyone wants to run an LS9 MAP sensor on an E67 ECM, they can now do it with this calibration.