I searched the past hour, but the threads don't seem to provide me with my answer. I just installed the X02 Dual exhaust on my 2008 nismo z, and WOW!!! what a difference in the sound. It was 420 bucks shipped, and it looks great. I wouldve went for the HKS but for that price I would rather buy other accessories to compliment my upgrades. I can feel a slight boost in the mid range (butt dyno). I recently put on the Stillen Gen 3 intakes on, and it was a good combo. However, will the exhaust quiet down after some miles are put on it? Also, my main concerrn was I think there is some raspiness at around 3-4500 rpms. Maybe lower, too. What can help remove or reduce this? Sound clips, if you understand, don't do much justice to giving you a solid answer. Would resonated test pipes or HFC's help? Based on your experience, if you have used both, do one or the other have their pros and cons? Looking to reduce the raspiness, which isnt too bad already, and gain some more power? Believe me, I searched before posting this thread because I am aware of the flaming that goes on. Just looking for honest help. Thank you. I am not able to post pics of the exhaust because it says there is a security token missing. Ive tried on 3 different computers with no luck yet. Maybe its the site. Anyways, I would appreciate some insight.

 

The exhaust will quite down after you drive around for a bit. I'm actully looking to get mine to be louder. Anyways, first put some miles on it then you will have a better idea of what you should do. Go with HFC's, maybe a x-pipe, I remember reading on here that it helps with the sound, but you have to get it welded to the exhaust.

I'm sure others will give their input.

 

Maybe you should try searching for hks exhaust, instead of xo2, that might produce some different results. But putting HFC's and test pipes will only make it louder, and test pipes will produce rasp. People say the hks is a raspy exhaust, so putting test pipes will only make it more raspy. But that might differ with hfc and the xo2.

Or, like the previous post stated, you could weld in a magnaflow x pipe, I heard it eliminates rasp and produces a nice sound.

 

https://my350z.com/forum/intake-exha...ds-inside.html

here you go

 

Congrats on the X02. You will realize a lot of people will bash it, but here in SoCal, we can pick it up from the eBay sellers for $200-250. Can't beat that. Plus it hardly rains here, so rust isn't a issue. Hell, The underbody under my car is still clean after 50k.

Even though I have a DE and you have an HR, I too felt an increase on the butt dyno.

Yes, there is rasp. I just installed resonated test pipes and it rasps HARD. It has that metal ringing sound. The solution? My plan is to add a Magnaflow X-pipe muffler (14386) in place of the X02 H-pipe and twin resonators. This should help bring the rasp down and bring some of the VQ sound back.

Here's my video showing before and after resonated test pipes. You'll hear the rasp. http://www.youtube.com/watch?v=CpkiOYiC7hQ

Here's some videos on an HR showing the X02 with Magnaflow X-pipe.
https://my350z.com/forum/intake-exha...id-inside.html

Hope this helps.

 

HKS exhaust starts to rasp at 6,000....as it should when you are on your way to redline. If you are getting rash below 4k then it's just the way the exhaust was built. You get what you pay for.

Test pipes and HFC's add more rasp.

also....OP post your dyno.

 

Sounds like I should go ahead nd do the x pipe. Now, is the xo2 also 2.5 inches? Assuming the other fellow added the xpipe to his xo2 system, is it a 2.5 inch? Also, where can I find this? On magnaflows website, or is there someplace else that I can find it cheaper? Thanks for all the input everyone

 

I will post my dyno wen I am home from a family friends Xmas party. I'm on my iPhone so I don't have it with me. Will do it asap.

 

You will never be able to completely get rid of the rasp sound. We all live and deal with the sound day to day. You just have to get used to it.

There are some ways you can make it quiter. Test pipes and HFC will deff not make it quiter. It'll all but make ur exhaust tone louder.

What I found to help keep the raspiness down is to put an aftermarket y-pipe in. The flex joints on there create a lot of rasp. (You can really tell where the rasp comes from when you blow a hole in the flex joints.)

The test pipes are good if you don't care about emissions. However, you can make ur car completely legal with the test pipes by putting the o2 extensions on the sensors going into the cats unless ur state makes you pass the sniffer test. I had HFC's and they ended up cracking from the heat and stress put on them and eventually blew out the honeycomb on the inside.

Honestly I love the rasp. I love the way it sounds at high rpm's and I don't notice it at lower rpm's.

 

The X02 is 2.5".

You can find the X-Pipe on Magnaflows website or you can go to www.performancepeddler.com and get it for $95.44 shipped. Search for "Magnaflow 14386".

 

Heres the dyno you requested

 

Is the x pipe flow built into this? Does this replace the resonators that are part of the H-Pipe on the Xo2 exhaust? The part seems pretty "long". And thats a damn good price!

 

This is what the inside of that muffler will look like. It's a muffler with a built in x-pipe.


This muffler will replace the H-pipe and the resonators of the X02 to reduce rasp.

 

Thanks so much for that response. The muffler shop near me is Hendricks autoworks and he does a superb job with anything. Is this a difficult thing to do? How long do you figure it should take an expert exhaust technician to do this?