This!!!It's probably been done, but as has been said many times, anything above 9-10psi or around 350-400 hp should really consider a standalone. Once you get to that point it becomes essential to be able to control timing, which a piggyback can't provide. With a standalone and a good tuner your car could be as reliable and drivable as a factory car, something that just cannot be accomplished with piggyback management especially at the hp levels you're talking about.
this is what im about to try! seeing as I have emanage ultimate readily available!Or use an emanage ultimate piggy back so you can retain all the factory functionality too.