Make sure your MAF is reconnected correctly, and that ALL intake holes are either connected to hoses or plugged. My KA24DE S13 was bogging for a while after I installed the intake.. there was a little place on the bottom of the intake for another hose to plug in, and there was no hose for it (the intake is for an s14). The un-accounted for air was making her bog. Plugged the hole with some JB Weld and now she runs like a top!