I have this same problem with hearing a rattling/hissing when letting off the throttle at around 2500 rpms. when I put the car up on a lift and had someone rev it, I could tell the sound was coming from the Y-pipe, not because the test pipes did not have the bracket. Now...maybe the Y-pipe went bad because the test pipes no lnger have said bracket, and that is causing the Y-pipe to rattle more. I ordered the Intense Y-pipe and we be putting it on Thursday. I will let you guys know what I come up with.

 

Sorry to hear you're having the same problem... we'll both have to post updates on this thread and hopefully our headaches will save a few other people from further problems. Good luck to you.

 

Now... I have the midpipe thing figured out. As far as the TP/HFC issue goes I've boiled it down to this...

Crawford HFC's
Ultimate Racing HFC's

OR

Helix SS TP's
???

 

If you're going for TP:

UTR Resonated TP; one of the best TP available for the Z. Sounds great, includes support brackets, and the TP's welding itself is a work of art.

 

Not bad... My exhaust is LOUD now... that can't be any louder. Haha...

I need to buy soon... I just don't want another rattle, hiss, or leak and I'll be a happy camper. Hmm... decisions, decisions

 

my test pipes have no brackets, mated to a Fujitsubo Y pipe and Fuji exhaust, and have 0 noise, 0 rattle, 0 issues whatsoever. The flanges are what determines if it fits well or not, the bracket is a byproduct, and not particularly important.

Good luck whatever you decide.

 

It seems like there are other members that have had issues with the Nismo y-pipe as well and are running different TP's or HFC's. Some members have gone through several combinations. I like the sound of Nismo... I believe they make a good product. I'm still having major issues though, and agree that the angle of the flange may be the cause (I believe I mentioned that in my first or second post in this thread).

My only reason for wanting to change the y-pipe out with one of a different design is simply because I don't want to take any chances. If I went with Fujitsubo or something similar it would essentially be the same thing I have on there now. I know they make a great product, but I've experienced problems, and so have others (even if it is due to the TP's and not the y-pipe itself). The y-pipe and test pipes are getting replaced... and hopefully I'll be done with the problems.

I'll keep everyone updated... still need to order a replacement for those TP's though. It's been a busy week at work.

 

not knocking ya at all, I totally see where you're coming from

 

It's all good. I agree with what you're saying. My exhaust is going over the 2k mark (and climbing), and I'm trying to not take any chances if I can. Haha

 

my Intensepower.com y-pipe will arrive tomorrow and will installed tomorrow as well. cross your fingers.

 

Good luck! I'm not sure when my y-pipe will arrive. No tracking number yet. Let us know what happens!

 

Well i have to agree with z1. Unless you are running big na mods, the y-pipe is not going to make a noticable differnce. Just stick your stock back on for now.

 

Uhh... the stock y-pipe is long gone, and the Nismo y-pipe is broken. This thread isn't about making power at all. It's about the bad rattles I've been having with the Nismo y-pipe on my s-tune exhaust and replacing the y-pipe and test pipes I have on there now.

 

i have the UR cats with the nismo exhaust and yes the shotty nismo y pipe cracked my cats at the brackets. Just get the JIC y pipe like everyone is telling you. The redesign of crawfords cat bracing WAS because of the nismo y pipe.

 

Yeah... I ordered the JIC y-pipe earlier in the week. It's suppose to show up on Monday. I'm crossing my fingers. I'm not sure what to replace my TP's with, but I'll figure something out.

 

so I had the Intensepower.com Y-pipe installed today and the sound is still there. The only thing I can come up with is that the cheap TopSpeed Pro-1 resonated test pipes I have on there are the culprit. I guess I'll have to switch to another brand and cross my fingers. Any suggestions? I'm not really wanting to spend a **** ton of money by the way, but at least something a little better quality than TopSpeed.

 

Man... sorry to hear that. If you have access to a set of ramps or a lift you might try getting under your car and see if you can replicate the noise. I put my car on a ramp and had a buddy hold the rpm's constant while I was underneath... that's how I figured out my y-pipe was done.

As far as TP's go davidv recommended Helix SS on the first page, and there are a few other recommendations in this thread. I'm currently running strup test pipes... the craftsmanship was excellent however the flanges were a little off which may be the cause of my problem. For now I'm thinking about throwing the stock cats back in until I can come up with exactly what I want.

 

well, I don't think Helix makes a resonated version of the SS test pipes. I might just go with UTR.

 

I tried to order a set of UTRs from perf nissan a couple weeks ago. They were back ordered.

So - My next choice(s) were Fast Intentions and Kinetix res test pipes. Both with life-time warranties. Both around the $350 range.

 

I know one of the problems I had with my Intensepower TopSpeed resonated test pipes were that the driver side flange that mounts up with the Y pipe was not flush with it. It seems when the test pipe was made, whoever welded the pipe to the flange was off about 4 degrees, so now that the test pipe is mounted to the Y pipe, there is some pulling/tension on the flex to compensate for that gap. Could be causing the problem.