Update: After much more frustration, I am getting closer to the problem. We ghetto-rigged a flip camera underneath the engine bay, pointed it towards my fuel pressure gauge, and then ziptied a flashlight pointing towards it. at the time, i had the stock fuel pressure regulator, and the fuel pressure was not holding under boost. it would drop back down to ~40. It would hold sometimes and other times it wouldn't. So I got an Aeromotive A1000-6 and did the test again. Same thing. So it's not the fuel pressure regulator. Only thing I could think of is maybe it's switching from 9 to 12 volts SOMETIMES and other times it's not, but I find that weird because I did replace my relay with the blue one. Would there be any problems with changing it to 12 volts ALL the time?

 

I wouldn't leave it that way... but it would be a very interesting test with your ghetto camera.

You should be able to jumper through where the fuse goes in.

 

well if your tune is inconsistent and youve gone this far with ruling stuff out, my guess test your map sensor on the intake mani, one of the things it does it help give readings to determine proper af ratio, i could be wrong about it being bad, but one more thing to rule out, now other then that: is the connector plug for fuel pump assy on securely? all fuel lines not leaking? your tps sensor working correctly? i say tps because it also helps determine proper af and timing because it corresponds to where your throttle body is at...no boost leak with the throttle body seals?? i know im not just ramblin just tryin to help a fellow boost junkie..
good luck