[BradSt]

You will gain ZERO power/mileage with a different filter, due to the way the PCM controls boost from the turbo. Stick with the stock filter.

 

[BradSt]

Buy an OEM AC Delco MANN filter...there is a reason it was selected over a Fram or Purolator.

 

[BradSt]

Could just use a MAP sensor, or an automotive vacuum gauge with a long hose...I have no doubt that an oiled gauze filter will show less restriction...That isn't even up for debate...but it WILL let in more dirt. When you have a system that regulates boost, based on calculated engine torque output, a lower restriction filter won't make a HP difference. Only thing I could see it doing is slightly lowering charge air temps, since there would be a lower pressure differential between the inlet and outlet of the turbo.