it should at least require a remap.
2 psi though isnt much and if you remain in the parameters of the sensors, and the timing advance/retard allowable by the computer as well as added fuel, then you will be ok. the thing is though, and am not sure of this.. but i do not believe 2 psi would not overcome the need of the engine at wide open throttle. meaning the engine will still be running NA at that point and have a restriction of the fan in front of it. I am sure there is some big formula (probably) but you have to remember the engine is a pump too. so you need to pump air into that pump (per cylinder) faster than it pumps itself.