They're interchangeable?

[thermal]

You have to consider several factors based on a power goal. Turbos come in so many sizes. You must look into A/R or trim sizes.... even bearing design. This applies to any motor out there. Boost is boost, but remember that pressure and volume varies per turbo size.... compressor blade design and housing A/R. In other words, 10 psi from a T25 is not the same as 10 psi on a T4. That mainly has to do with volume. This will also affect where the power peak will be on the RPM band. Meaning, on smaller turbos, 10 psi can be achieved sooner on the lower RPM range vice bigger turbos on higher RPM range.

Basically, there is a formula that tuners and designers use based on where they want the power should occur. They must also consider the CFM of both the motor and turbo.......