Varies for every car.
An engine is basically a vacuum or air pump, the more air in the more power made. Psi is resistance to flow. Flow = power.
For people that dont understand what im saying, let it sink in for a few.
If you can make less bends in the ic piping, port the head, whatever can be done to flow more air, you will make the same power at lower boost levels due to less resistance for the airflow.