I have had the same exact problem at the same RPM and I do have an EM (Cobb AP). I too am running the Invidia down and uppipe with an SPT intake and catback and am still utilizing the O2 sensors in their stock arrangements. I do realize, now that I've bought and installed it, that my setup might disagree with the intake. But, according to Cobb, the intake disadvantages take effect when, at the position of the MAF, the tubing is a different diameter than stock or causes airflow turbulance. Makes sense, right? But the new intake, when compared to the stock air box, appears to be the same inner diameter and provides a smoother path through which air can travel. Unfortunatly, it seems that there is no way to custom adjust boost psi with the AP's use of pre-calibrated maps- unless I'm just not getting it. Anyone know the "fix"?