k, i was going to buy a evo2 cat/back for a gs-t ... i know the bends are the same, but i wanna replace my cat as well... i plan on getting the rest of my setup to be 3inch so my question is this.. will this setup throw a code for the downstream o2? and if it does, is there any way to bypass it? resistor maybe? also, since i am going 3 inch the whole way, couldnt i get a gst cat and have them put on a new flange for the dp to mate the gst cat?

you shouldnt get a CEL unless your o2 sensor is fucked up

cool... so ill get a hi flow gst cat and the evo2 then? do the gst cats even have an o2 bung? or do you think maybe even a test pipe would be pretty good?

i have a pacesetter high flo cat and greddy evo catback

the o2 bung is in the DP and the catback has a bung for the downstream sensor

cool.... where did you get it? i was also thinking of the apexi n1 but i think ive made my choice! did you have any issues with fittment? bolts lined up?

i have the tanabe racing medalion catback with apexi test pipe and it sounds mega tizyte do0d. 3" piping back!

I have a 3" high flow cat from BombZ racing and a 3" Greddy Evo catback - sounds very mean, and the best part ... not very loud at all. Car made boost a lot quicker with all the 3" piping.

i had no problems getting mine in
the pacesetter cat and evo exhaust bolted right up
and used all of the oem hangar places

it is one of the few things that fell right into place on this damn car

i am not so sure on the pacesetter
it works but i dont think it is the best cat out there

If you have the hahn kit get their 3" downpipe ($375) and you can also get a nice cat from them, and the Flange you're gonna need to change the 2 1/2" to 3" at the start of the EVO2 inlet

hahn eliminator DP part #HEX-4700 $375.00
FWD hi-flow cat converter. Part#HEX-6250 $225
they will modify the cat to fit the 3"catback and DP

if you are interested in their thermal research exhaust
HEX-1300 exhaust, we modify to fit the 3" cat . $599 for the exhaust and modification.


per brad in sales at hahn
most 3" exhausts come with a 2-2 1/2 inch inlet to bolt to a stock size cat

they put on the flanges to allow for a full 3" from turbo to muffler tip



are you getting the 3" greddy for a GST
i have yet to find the evo2 in 3" for a NT