Hey guys Im new to cars and I have a few questions that I cant seem to find the answer anywhere to so I guess this is my last resort. I have a g35 2007 journey SEDAN with the VQ35HR i cant stress the sedan part enough but finding parts for this car is impossible i cant find anything that is not 300+ so my question to you guys is I am looking to buy test pipes for my car just some basic cheap like 100-130 not resonated (because in my state my car can be as loud as I want). Do all testpipes made for the VQ35HR fit for the sedan? are they universal? because there are tons of 350z's with the same motor that have cheaper parts I think. My final question to you guys is my roommate has a g37 coupe that had the y pipe replaced he told me I can have it if it fits my car do you guys think it will fit? Will it change the way my car sounds in any way?

 

I wouldn't use the VQ37VHR y-pipe, it has a smaller diameter inlet that was presumably to meet stricter emissions.

As for the HFC/test pipe interchange, '07-08 350Z with HR, all 370Z, '07-'08 G35 sedan, and all G37 use the same catalytic converter. You could get test pipes/HFC for any of those and they will interchange to your HR sedan.