That has gotta be the dumbest shit I've read on SAU in quite a while and it didn't come from the skidmark sadly....
A few questions...
A) Why are you getting caught up in "boost pressures"? Who gives a f**k about boost pressures! Would you wanna make 500kw at 30psi or 500kw at 35psi? Boost pressures DO NOT mean more power.
A more efficient motor/setup will make the same power on less boost so that is absolutely meaningless!
B) Does the turbo you chose make the power you aimed for?
If not guess what?
Its time for a BIGGER TURBO!
C) Does it not drive better than anything you've driven before and any mates or family members non EFR cars?
IF you answer yes. THAT IS what these turbos are all about.
Even if you use a smokey old precision or a GTX and "overspin it" its gunna drop its guts out the dump pipe just like any other turbo will if being used outside of its efficiency range. Just so happens the EFR is more sensitive to this fact!
Instead of wasting your time on silly posts like that & wanting to throw endless amounts of boost into your stock motor, chuck a $200 speed sensor in your compressor cover and see where your speed is at and see IF you can turn the wick up some more SAFELY!
If not throw a shitty PTE on your car and enjoy topping your oil up regularly!