you can get a hi flow cat welded. but where are you going to put it? the only way you can get the set up you are looking for to work (meaning you want to have both the primary cat, the secondary cat, a header system, and no CEL) is to go with a shorty header, downpipe with cat, and midpipe with cat. wagner motorsports actually has the parts. here's the caveat. it's around $500 for the shorty header. $475 for the downpipe with cat. $350 for the midpipe with cat. all cats are high flow.
the MIL fix will get rid of the O2 sensor warning. so if your cat WAS to go bad, you'll never know. but it is independent of any other CEL you might get. this modification is for the O2 sensor only.
i think you are mistaking your primary and secondary cats. your primary cat is the drum-like thing sitting right under your heat shield right now if your car is stock. getting a header will replace all that restrictive tubing up to the secondary cat. the secondary cat is the thing that you bolt your catback exhaust up to and is also where you would hook up your header. this point is also where the midpipe is.
so a brief descriptive schematic of your exhaust if you are completely stock:
exhaust manifold --> stock header (which is too short and too crappy) --> primary cat --> downpipe --> midpipe --> secondary cat --> s-pipe of the exhaust --> axle back exhaust section.
with the ractive header, it will go:
exhaust manifold --> header --> midpipe --> secondary cat --> exhaust piping.
hope this helps. i got a little turned around with the two options of elminating the CEL. but it's pretty clear now. you can either get the MIL fix, or you can rewire your second O2 sensor to s-pipe of your exhaust AFTER the secondary cat. the O2 sensor will now see catalyzed exhaust instead of the raw stuff. either way works.
Subghetto said:
So I guess that any header that we get for are car will require a MIL eliminator :mad: . I have a couple of questions: would it work if I got a hi-flow cat welded on the header some how in order to avoid the CEL ? And if I get the MIL fix since it gets rid of the CEL will it get rid of it eternally so as not to show up if another problem arises or perhaps cause other engine code malfunctions or problems for using it? and if I decided to not get rid of the primary cat for now and instead opt and get a custom downpipe made with flanges to replace the 2nd cat so i can bolt it on and off for emissons testing, Would I pass emissons with only the primary cat? Get a CEL? and how much performance would I gain doing this?