I've been looking to upgrade my stock cats for some time now on my 2004 g35 sedan. My goal is to increase power without drastically increasing noise while still being able to pass emmisions. Fast Intentions seems to be the only company that makes resonated HFCs however they only guarantee compatibility for the g35 coupe and 350z. I called Fast Intentions to ask and they said that it should fit fine. Based off of my research the g35 coupe and sedan cats are the same so should I have any issues getting the part installed? This is my first post so I apologize in advance for any mistakes and I Appreciate any help!

 

They should fit fine but be warned, your car will be significantly louder and you introduce the possibility of rasp forming by adding them to an otherwise stock exhaust. Your call.........

 

I went with the FI resonated HFC for an '08 350z for my '03 sedan. The DE flange fit my setup perfectly. I have quiet, deep tone up til 3k then it really starts sounding alot like a modded z. Little to no rasp, they bolted up without issue to my DC headers and hr y- pipe. I would highly recommend them to any sedan driver looking for quality resonated hfcs.

 

They will fit fine. FI makes very good quality products for our cars.

I rocked FI high flow cats (non resonated) for quite some time with no issues.