I currently have a quite few mods on my 2004 GT and the next thing I wanna do is upgrade the exhaust. I have been looking at SLP Loudmouth II mufflers or a whole cat back system, I have also been looking the MAC Prochamber CAT Back system. Header wise I have really only been looking at the JBA set since they are 50 state smog legal and since I live in the wonderful tree huger state of CA I have to stay smog legal. I would also like to upgrade the H-Pipe I have on there now , I would kind like to stay with an H-Pipe since the sound is bad *** and the x-pipes sound kinda raspie.

Keeping in mind I need all the O2 sensors and need to stay smog legal can I get some recommendations please. The sound coming from exhaust is ok just added a set of 2-Chamber Flowmasters and still running stock headers and H-Pipe.

Mods currently:
Demon CAM
Roush Heads
Diablo Tune
BBK 75mm TB
C&L Upper Plenum
BBK Cold Air
many many interior, exterior and engine bay bling blings for car shows

much thanks

Matt

 

Forget the O2 sensors if that is what is holding you back on smog stuff. I am in Northern Cali too and am running a Basani X. I just kept the stock H and will throw it on come smog time. From my understanding, your smog probably won't pass with regular high flow cats anyways. I plan on trying to get it smogged with my setup, if I don't pass, back to the garage to throw the old setup back on.