Trevor Tate

I just recently got my Z. It has Nismo cat back exhaust and the flex pipes in the Y pipe are leaking. I was wondering which Y pipes would fit my 2003 350z because the mechanic confused the crap out of me. Thanks.

MicVelo

If it's an S-Tune, you'll need the S-Tune Y-pipe (or appropriately sized afterrmarket performance setup). Any OEM pipe will fit (so long as the pipe gaskets fit properly) but will not give the performance of the S-Tune due to the pipe sizing.

You won't find an S-Tune Y-pipe though so if you want to maintain the performance, suggest going with a good aftermarket unit like the Motordyne XYZ.

https://www.z1motorsports.com/exhaus...on-p-7306.html

Trevor Tate

Ok cool thanks. The mechanic was confusing me because of the sizing. Making sure I didn't get a bad Y-pipe. Thanks for your help!

dboyzalter

iTrader: (3)

https://my350z.com/forum/intake-exha...e-catback.html

Here is a discussion on the matter

Trevor Tate

Would this Stillen work? Not looking to drop $400+ right now.
https://www.stillen.com/stillen-2003...pe-504252.html

MicVelo

No personal use but I don't see why not. Specs are pretty much same as the S-Tune. There's other ones out there as well....

https://conceptzperformance.com/item...9&page=1&all=1

Some a lot more expensive, some a lot cheaper but all with identical sizing specs. Granted, the cheaper ones may fall apart in less time but they'll work for a while and probably "long enough".

slicnicz33

I bought my car with the same setup , and had to replace the y pipe after a year due to the flex pipe fraying away from all the scrapping.

I first went with the Megan Racing z33 y pipe but then after researching a little I found that the y pipe (oem and aftermarket) for the 370 had much better flow due to a design change. I exchanged mine for a MR 370 y pipe and installed will no issue other than the nuts were all rusted and I had to soak them in bp blaster for 30 min prior to removing them.

Brand is really a personal choice for aftermarket y pipes, the best flowing y pipes ( and large diameter as well) don't bend rt after the cats but rather run straight and then bend rt before the mid pipe. If you doubt me even Nissan themselves changed their oem y pipe design from the z33 to the z34. Google it

Side note, after removing the y pipe , start up your car , rev it a little , sounds real nice . Make a video or two .

terrasmak

iTrader: (8)

Any Y pipe will work from OEM to motordyne. Best gains, motordyne or one with a similar merge point, but gains are really not a huge deal if running an S tune

dboyzalter

iTrader: (3)

Dont bring that mess around here Evan...

They changed the y pipe in 07 + and it wasn't a big improvement, you also need to remove some plastic pieces from the 03-06 in order for them to work...

If your thinking that the updated y pipe is going to make any difference your fooling yourself.

Kileak

iTrader: (4)

My S-Tune y-pipe flex are leaking as well so I switched back to my OEM temporarily.

I will likely just get replacement flex joints welded in place instead of getting a whole new y-pipe. Surprised you couldn't just do the same. Any stainless steel flex joint of the same diameter and length should do, wouldn't it?

dboyzalter

iTrader: (3)

Or if you got big brass ones you can have no flex joints like me. But I would assume that you could, but also would guess getting a new one wouldn't be much more expensive.. Getting stainless steel welded the right way isnt cheap. And im guessing stainless flex pipes are also pricey.