I have had test pipes for about two months with the rasp(~6000mi). I just a Stillen CBE on and it is worse! It is driving me insane, I think I am going to put my cats back on and deal with the loss. I was playing with the thought of header wrap all the way back to the muffler, starting at the test pipes....

I spoke to Berk a lil while ago and they said that the rasp is expected. I sent him my youtube clip and they confirmed it.

i had rasp on my old 350z i had TurboXS Test Pipes

There will always be a rasp with test pipes&high flow cats...

I hate that rasp sound and I was thinking of getting high flow cats as well. FIY, the "washer mod" is very raspy when cold but disappears as the car warms up.

Chops, I just listened to this clip and my nismo USED to make the same noise after I installed res tp from GTM. At first I thought it was coming from the tps but wasn't. When it was up on the lift we heard the noise coming from the h pipe. Like something was inside there. (Like a babies rattle) Just right around 3gish hold the gas pedal. The noise is steady even on deceleration around the same rpm. We all couldnt figure out why.Maybe because it has no back pressure and NISMO h pipe is only 2" - 2 1/8" But I came up with a cure. We removed the h pipe configuration and my guy build a 2.5 X pipe CB. The noise went away completely. Freed up power and sounds throaty. Im thinking you guys both have the factory Nismo cb with your tps and that's where your noise is coming from. Hope this info helps.

interesting...any pics of said X-pipe? i wish there was a nismo compatible X-pipe. id rather not get rid of the entire nismo exhaust

You dont have to. Heres 2 1/2 piping w X pipe. Replacing Oem 2'' H pipe. Stiil keeping the Nismo muffler and resonators. Sorry for the delay. I mainly got this done because of the lack sound,restriction and budget. Also because of the rattling noise @ 3 grand Rpm. That was really annoying. Paid less then half of a full CB and satisfyed for now.:tup:
http://i55.photobucket.com/albums/g1...s/IMG_1742.jpg
http://i55.photobucket.com/albums/g1...s/IMG_1744.jpg
http://i55.photobucket.com/albums/g1...s/IMG_1740.jpg


Factory Nismo H pipe
http://i55.photobucket.com/albums/g1...s/IMG_1745.jpg

Nismo H pipe flange 2"
http://i55.photobucket.com/albums/g1...s/IMG_1748.jpg

Nismo Flex pipe flange 2 1/8 "
http://i55.photobucket.com/albums/g1...s/IMG_1749.jpg

Can you please post sound clips of your setup with said X-pipe?

Thanks for the info, I'm planning on doing this as well... I wish someone would manufacture the X-Pipe other than Amuse (which costs $1600), I'll ask a shop to fab it for me.

antfd3s
 

Might the fellow who constructed your Nismo's X-pipe offer these for sale to interested Nismo owners?

I've sent an email to Fast Intentions inquiring about having them fab up an x-pipe for me to hopefully resolve that damn rasp/rattle. I wanna keep the Nismo exhaust but don't wanna pay $1700 for the Amuse pipe. We'll see what they say...

Look into the exhaust section. I posted a thread in regards to this and some of us are waiting to see if FI can do this for us for a reasonable cost.

http://www.the370z.com/intake-exhaus...ent-nismo.html

i talked to Tony and he'd be happy to custom build one for me. it'd be about a quarter of the cost of the amuse pipe, but you have to go to him. which isnt tough considering you're already in ventura county. i was planning to make a trip down sometime in the coming months and he was on board with it (but its a 700 mile round trip for me, gas is a bit**). give him a call...they're in northridge, which is an hour from you!

Yea I'll definitely give him a call. I'm actually like 15 mins from him so that would be perfect. I'll definitely keep you guys in the loop.

lucky you. i was hoping to be the first, but you can definitely go ahead!:tiphat:

I spoke to Tony and he said he would do it, but was pushing his TDX instead for like 500 more than it would cost to fab a custon x-pipe. I really am on the fence with doing just the x-pipe or changing the exhaust out completely. He said he couldn't guarantee the rasp would go away after the x-pipe was in because he hasn't done it to the nismos yet... What do you guys think?

thats totally upto you. for me i would definitely pony up the cash. hell i think i was quoted 500 for it to be done, and fuel costs would have been 150 for me to get there and back. i forgot to say..reason i would do it is because where i live, you are harassed for everything on your car. especially with the huge wing on the back of our hatch. i want to keep my exhaust looking as stock as possible! im also lowered, so those TDX cans would scrape everywhere i go!

keep in mind, the H-pipe is about a 2" pipe, then after the H-pipe is a 2.25" pipe to the resonators, and after the resonators it widens to 2.5" to the muffler. from having my car on the lift by a fellow Z enthusiast yesterday, he said this would create some nice backpressure, i'm likely going to have sonic motorsports fab me up an X-pipe from mandrel bends now. plan is as follows:

2.5" pipe from cat-back to X-pipe opening, then other end of X-pipe will be a 2.25" pipe to the flange of the resonator. this keeps all the stock widths, yet widens the area where there is the most restriction in our H-pipe. i'll post videos/pics whenever i have this done :tiphat:

:tup:
Thats a great plan you have!
I think i may wait a bit until I see more videos about people that have done this, to ensure that the rasp will go away entirely with the x-pipe alone. I really wanna keep the nismo to keep with the nismo theme on the car, but the rasp drives me crazy sometimes! Time to save a bit more cash money! Good luck with that fab work! I definitely wanna hear about it once its done! :tiphat:

Heres my story..
Guys, I don't think there's no way around the raspy sound. Even when I intalled a custom xpipe the rattle was gone. But the exhaust note wasn't the same. I expected it to be louder and have more of a grawl to it .. Now the problem was with exhaust note. The muffler gave me a raspy note. Like the muffler was getting to much air flow. It couldn't handle the power. Causing the sound to be a lil ricey. My exhaust guy that made the x pipe suggested removing the resonator section then going with 2 1/2 flaged resonators (either 12 or 14 ") and still use the Nismo muffler. SINCE I to didn't want to take the look away from my car. This is when my back was against the wall and choose to get a Catback from FI.
Now just a little info on this situation. THE RASP GOT LOUDER! lol the muffer tips don't stick out enough passed our bumper either. Also the xpipe section is 3 pieces! Why not make it 1? (So it can all fit in 1 box to ship was my guess)
The only thing I like is the sound while accelerating. Not happy w spending mad money and waiting 3 months to get it either. Back to the baby rattle/rasp. Its so loud I wanna take everything off and go back to stock and regroup my thoughts.

No way? The rasp got louder with the FI exhaust?! He told me it would eliminate the rasp completely! He even said that he would give a money back guarantee if the rasp was still there! Now i really don't know what to do...I read for some the rasp went completely away with the FI exhaust though.

Do you have a video by chance?

The rattle on decel is what I mean. Around 2 grand. From 1 to 10. Its an 8. Sorry I get those 2 mixed up
Its so loud after the install its hard getting used to. So I read and asked questions why? They all say its from my res.Tps. No back pressure and its just air making that noise the motor creates. So my other question was, "is there anyone making a Tp that stops this Really anoying rattling hissing noise that wasn't there to began with? My 300,350,FC and Fd never did it. They all had catbacks w tps. Wth? Sorry im all heated up im just tired of throwing my money into this car and creating new situations that weren't there from the start. I feel embarrassed driving it sometimes. I guess hfc or stock cats will eliminate some rattle. Dam this motor. Lol

I haven't mastered posting vids on here yet. Maybe I can send it to you and you can post it for me.

The only other suggestion was one that I was planning to do. I was going to take my OEM H-pipe to a fab shop and ask them to follow the rough path and bends but with 2.5" pipes all the way and install (2) Vibrant resonators somewhere in there as well. Our VQ engines are not the only ones having this issue when freeing up the exhaust. I have read that the newer BMW M3 and other high compression engines have this rasp as well.

I am pretty sure that I would agree that it is the TP's that causes a lot of the raspiness. The choice is either resonated TP with stock muffler or aftermarket exhaust with stock cats...these combination's seem to be the common theme in people not getting that rasp sound in engined deceleration.

The resonators will only dampen the sound a bit though....I am sure that it will still be there...just a bit "softer".

Currently I am running GTM resonated TP's, joined to Sunline H-pipe, ending at the Amuse Nismo Extra Silent exhaust. It does have that rasp....quite a bit. Eventually I am planning to make some adjustments to the Sunline pipe and see how that goes. The flanges were crooked anyhow...so I have to cut it anyway.

Does anybody have any opinions on whether the nismo exhaust with the FI resonated HFC's still has the rasp sound? Or does anybody have this setup and and a sound clip? I have 2011 nismo with K&N typhoon, and I'm undecided whether to purchase the FI resonated HFC's. Need some advice guys

Birdmanx1 had HFC's with the stock Nismo exhaust I believe. Scroll through his journal, I think he has a sound clip in there.

http://www.the370z.com/members-370z-...o-journal.html

Thanks alot man, for the info

Now, I'm really interested in the Fast Intentions HFC's, but Im not sure which one should I get, the normal HFC's or the resonated HFC's? Need some help guys.

Regarding the raspy sound: the Nismo is Japanese...

True I agree, but now would you guys think the Fast Intentions Resonated HFC's would reduce the rasp? If so, how much would you guys think it will be reduced? Also, should I just go ahead and purchase the Fast Intentions Resonated HFC's or just the Normal Fast Intentions HFC's. Need some advice before I purchase them this week

I think you meant hfcs vs rtp?
Its really up to you. Your still gonna have rasp w both regardless. The hfc will eliminate mostly all but will restrict flow and power.Rtp will give you a bit more rasp(not much noticeable )and free up more power and flow. I personally like more power and flow. This car after awhile ALWAYS needs more power. You wont notice rasp until the higher revs anyway. Not everyone puts this dd to the pins every light to even notice. Thank god it doesnt sound like rice a roni.

Check this out

HFC's

Fast Intentions

Resonated HFC's

Fast Intentions

Any thoughts on which ones should i get????

I know this is a dead post, but I just installed my Berk's HFC's testerday.....To say the least, I am dissapointed. Seems like I gained a little bit of low end power......but the rasp is embarrassing. I have Stillen G3 intakes (dont think they would effect this), and the Stillen CBE. It sounded great before the new cats, but like all of us I wanted more power.......When the RAsp is not there, it sounds much more agressive, in a good way. When the RASP is there, all i hear is a coffee can civic, but unfortunately, its my Z.

If you can get larger resonators on your exhaust it will help a lot. I have the z1 hfc setup with a Fast Intentions exhaust. I started wi a 12" resonators. It was loud and sloppy (but actually sounded good -very mean). It was too much though and I went to an 18" resonator. Night and day difference. It is not as loud and has smoothed out quite a bit.

I have Berk HFC and stock Nismo exhaust. Rasp is gone but I have a rattle, not a rasp, at 2 k rpm on decel. But it's not loud and when I'm driving I can't hear it. If I'm in the garage with windows down I can hear it. It comes from the back of the h pipe. It's some weird resonance with the heat shield. Next oil change I'll have the tech poke around and see if they can bend it. Oh if you have an intake and HFC you really need a tune.

I have the FI resonated HFCs on stock nismo and no rasp at all.

One thought (sorry if it's been covered) but is it possible you have a leak? Most likely at the manifold/hfc joint.

I would HIGHLY recommend the Z1 gaskets. REALLY quality metal gasket that all but eliminates any chance of leak, and cheap.

Wouldn't the SES light kicks in when you have a leak? Hope it's just loose exhaust heat sheld.

No, I had a whole new H pipe put in with the OEM gaskets. But I'll have them check the joints/gaskets and the heat shield on my next oil change. It only happens on decel and at 2k rpm. I really can't hear it while driving. So its not that big on an issue for me.

I went from the factory Nismo exhaust and Berk HFCs setup which was raspy, to a FI CBE with the Berks HFCs. 1) To see if the guys at FI could prove that there would be zero rasp, 2) To go with a louder exhaust, 3) I liked the look of the cans from back, and 4) seemed that many people on the forum loved the product.

I now have no rasp, only the hiss on hard accel and lower rpm decel, which is typical of the car.

I had the FI resonated exhaust, but it was too loud for me and I went back to OEM Nismo. When I had it no rasp or rattle. Some hissing...

I also have that rattle. Glad it's not something loose. It's pretty consistent and I only notice it when starting the car up cold... once it warms up, no more rattle.