I just got a cat back exhaust system with glass packs, I love the performance but its not loud enough. I heard that replacing the cats would make it louder? but if i do that than don't i run into o2 sensors problems? I got a 02 fx4 with a 5.4l, i currently only have a edge programmer and the exhaust. I am thinking of getting a s&b CAI, or doing the Gotts intake mod. is the Gotts intake even give you any more performance? or is it just a wast of time?

 

i havent done the gotts intake and havent heard anything about it, but i dont see how it works

as far as the cats, you have a 2002, same year as mine, the best thing you can do to avoid o2 problems is, cut the pre cats (small ones) off and just leave the rears or cut all 4 off and get 2 magnaflow high flow cats

i ran a super 40 with just the rear cats and never had a light, then i ran with no cats and of course got a light, then i did my true duals and got 94106 hi flows and went to my work and cleared the light with the diagnostic computer

 

Hi-flow converters will do the job no problem. Part #94106.