Hi guys, I currently have a straight, no cat pipe which is connected to ractive 4-2-1 headers. I bought my car like this, I noticed the check engine light is on, I got it checked, turns out my car uses two O2 sensors, and I only have one, which is connected to the headers. The other belongs in the cat. Because of this, I think my car is running way rich because the headers have like a burnt purple tint, and the exhaust note coming from my muffler is insanely loud!! I was wondering, do you guys think if I buy the cat and connect the 2nd O2 sensor that my car will change the extremely loud noise to something more like a nice deep note, and at the same time help with my power by not running the car too rich? Also, besides a mini-me or turbo, what would you guys do to a d16y7 to squeeze a little power out of this little engine? Thanks in advance.