Anybody have any insight on this? I'll post the dyno run sheet so you guys can see this run plateau vs the 5psi from a while ago.
That's strictly a programming issue, and the bad news is that may not be something that can be dealt with. Without seeing the program log, my guess would be the turbo is boosting the manifold pressure too high. The MAP sensor detects this, the computer decides it's too high and shuts it down. In the GM world boosters will use a 3-BAR or even a 4-BAR MAP sensor, and use a program like EFI Live to program it. I think SCT offers a similar tuning package, you might contact them and see if their tuner will allow you to convert to a 3-BAR MAP. If the programming can be made to accept the new MAP, then you won't have any problems.
Now if this is something that can't be dealt with because the programming can't be made to allow it, there are a couple of other possibilities. You might be able to put a cheater between the MAP and the computer that cuts the signal by half. Unfortunately, exactly how such a device can be built is beyond my abilities so I can't offer any direction along these lines. If one can be built, your tuner would then have the equivalent of a 2-BAR MAP, and can tune the computer to work correctly with the altered signal. Doing this MAY also require a 2-BAR MAP sensor to work. I don't mind telling you that I'm not a fan of altering inputs, but in this case since the change would be a set, linear change to a single signal path I don't see it being an issue. Voltage parameters would also need to be altered by the programmer so that a failure can still be detected. In any case, locating a turbo-centric forum is where I would start investigating this. They may not have Lincoln-specific information, but MAP sensors work the same no matter the make.
If the MAP signal just can't be dealt with, you can look at just tossing the Lincoln PCM altogether and install a Megasquirt computer system. A Megasquirt will let you run 100PSI or more if you can get the engine to hold together, and can accommodate almost anything you can come up with. If you go this way you'll need to look at what inputs are needed to keep the Lincoln PCM happy so the auxiliary systems will work correctly, like the air conditioner and whatnot. For this, it would just be a matter of piggy-backing the Lincoln PCM feeds onto the Megasquirt system, or just running dual sensors. The Lincoln PCM will also need to have its error codes dealt with so as to not flip out when it discovers that it is no longer actually controlling anything.
Hope some of this helps.