OK Lithium, that fills in the gaps, it is always easier to make suggestions when you know the whole story. The 12 psi wastegate actuator spring may well be too high. You really should refer to your compressor map as it depends on the airflow that turbo develops at 12 psi. I have a number of T04E maps, what trim is the compressor? I have 40, 46, 50, 54, 57 and 60.