Originally Posted by ripto
One thing I haven't seen many people do is change out the cat, and I can't figure out why. Everyone seems to stick with a cat-back system. Joey D, VH5150, ShogunSamurai2005, how come you guys didn't swap the cat as well?
Edit: macatron, good to see a fellow CT'er here!
The primary catalyst is integrated in the Exhaust manifold. Some people (FocusBoy58 comes to mind) have changed the exhaust manifold with one of the catless aftermarket pre 2011 2.0 L duratec headers, but if you were concerned about emissions and or vehicular inspections its best to leave the main cat alone, although PZEV vehicles have a secondary catalyst behind the first one and ahead of the resonator and mufflers.