Boost levels; factory intake and exhaust

Hi guys,

A question in reference to our OEM air intakes and exhaust systems. Assuming we tune boost levels upward from factory 8 psi, at what point do the above mentioned start to become restrictive, if at all? I have read up to about 14 is fine, 16 and up is where gains, albeit small ones, can be enhanced with aftermarket performance intakes & exhausts.

Any shared experience would be greatly appreciated, thanks.

I am not convinced on the value of intakes except for very high boost cars but 17PSI seems to be a good crossover point to get downpipes. Exhausts at the end od the stream (mufflers) don't really do much of anything but do sound nice in a lot of cases. My car without intake or downpipes is tuned for 16.5psi max with a safety setting of 17psi. At my settings downpipes should add 15-20WHP but with the car under warranty the hassle & smell are not worth it for a DD.