Yes I've done the requisite search, and no I haven't found a clear answer to this one:

I have an FD with a 3" catback that came with it <i believe a Greddy SP> I'm about to add the following:
HKS DP, Pettit MP, RE Amemiya intake, torque brace, HKS EVC EZ, Pettit cool charge 2 SMIC, Cosmo fuel pump... Obviously I'm gonna get boost creep from this wide open exhaust, however I'm also going to be using a Knightsports 4beat REDOM ecu that is supposed to be set for all the airflow mods listed and 14.7 PSI. So I guess my question is, will the boost creep associated with opening the exhaust up exceed the 14.7 psi, the figures I saw were like 12-13 psi all the time with the waste gate being actuated directly sans pills, so i would imagine I should be able to control the boost where It needs to be at 1 bar. Otherwise I'd rather tear the turbo assembly apart to port the WGs rather than doing half the dp/mp work twice...Unless the waste gates can be done on the car?

 

Take it apart to do the wastgate porting. If you take the housing to a machine shop, tell them to bore the hole to 1.24 inches. Yes this should be done , do not take any chance of boost creap.