How did you get it out?? I checked both before install. Shook them both and no rattling. I believe it's a failed weld and the screen on the inside of the resonator is making the noise ..

Update: The rattle that I described earlier in this thread was NOT caused by contact with a bolt. It was coming from the exhaust system itself. However, after a few days the rattle started to die down and now I can only barely hear it during a cold start.

It is if you have an exhaust that has flex sections like our Invidia. People have been cracking Invidias using test pipes or HFCs without the brace. Getting a replacement flex section. Cracking that in a month. Getting another and then reinstalling the brace and never experiencing another crack again.

There's a thread about this from esfourteen. You have to install the brace back on.

Edit: And notice how everyone talking about rattles has an Invidia? It's no coincidence. Without the brace, you're putting too much stress on the exhaust's flex sections.

yea i read that thread. I just went by Tony's word and didnt put it on. Maybe that's why im hearing a possible leak that started 2 days ago. Will get under the car tomorrow to check it out. Will a leak at the flex joint cause the SES to go on?

Also, did you guys contact Invidia directly for the replacement flex joints?

Any picture how the brace is attached as when I ask my installer to put it on he said it's not possible some alteration is required. Does it need some new support points?

sorry to hear about that :(

You're right doccam. The ART pipes doesn't have the flanges to accommodate the oem braces. Hmmmmm.

Here's how it should look with the braces on.

http://www.amsmotorsports.com/shop/m.../berkcats1.jpg

anyone knows any solution?

Anyone have these matched with the HKS HI POWER????

I'm trying to rid my car of rasp and can't fins anyone with this combo. I'm leaning towards swapping out my HKS for an FI exhaust....

Regardless I'll be buying these ART pipes very soon. Just hope theres no rasp with the HKS.....

Wait, the brace cannot be mounted back with the ART Pipes? That's not good.

When I was under the car for the install, I don't remember seeing a way to install the oem bracket

so how people are installing it, the ones who did?

Well, they are technically more than strong enough to support themselves without the use of the OEM exhaust braces, especially when you consider the Art pipes weigh less than the OEM cats. But it is definitely extra insurance and was one of the things I like about my Berk HFCs, you don't need those braces to properly install the Art pipes however.

I was refering to installing the braces, I already have ART along with invidia running strong, but just want to install the brace for future hicups:icon17:

Test pipes are lighter than ART Pipes and they are known to crack exhausts like the Invidia if they aren't mounted with the brace. I don't think weight plays a factor.

We use ceramic beads to polish the pipes. Some of them may have found their way inside the resonator. In any case it is covered under warranty.

edit - We are now using a new fixture to keep the polishing beads out of the pipes.

There shouldn't be any rasp. I just went from test pipes to ART Pipes and the rasp wen't from disgusting and unbearable to virtually non-existent. :tup:

I am having this same problem from my passenger side ART Pipe. It sounds to me like the rattle is coming from the pipe itself and not the resonator, but it's hard to pinpoint it exactly. It is definitely coming from the art pipe though and it's not hitting on anything on the car..

It sounds like what Tony just said.. a small metallic bead or something bouncing around.

Thank you! :tup:

IMO the brace should be used with any pipe. Art pipe or not , and exhausts have alreay broke with them right ? So I guess you can assume it is needed.

what exhausts have broken?

ive only heard of Invidia breaking? So maybe the problem lies with that exhaust moreso than the TP or HFC's etc

The test pipes tilt up and down with the motor, and if you have an exhaust with a flex section like the Gemini, it will tear.

I'm going to cut and weld the mount tabs from the OEM cats to the ART Pipes. I don't want to risk an exhaust leak, having to replace a flex section, headache, etc. - so I'd rather just do it right.

i understand what your saying. but what im asking is which exhausts have broken other than the gemini?

People are making it sound like any exhaust with flex pipes will break because of this. What im saying is that so far it sounds like onmy Gemini's have had issues. And someone also had an issue even without TP's. So im thinking the issue lies with the Invidia's, not anything else.

^^ This.

Let me first say that I don't know about the exhaust tearing, and haven't looked the issue up, so there could be some ignorance on my part here.

No offense meant, but isn't Invidia a company that makes inexpensive substitutes? It sounds to me like an issue with the exhaust. The whole point of a flex pipe is so that it can flex. These motors don't torque around THAT much so I can see no possible way of it torquing the pipes enough to mess up a flex pipe section, unless it's poorly made.

If anything, putting the support bracket on the ART Pipes will be a bad idea (if even possible), because that will disallow the flex joints to do their job. If the ART Pipes are rigidly in place and the engine flexes some, you might break the welds on the ART Pipes where they meet up with the headers, or most likely the welds will break where you added mounting tabs for the OEM cat brace. The OEM cats can handle this wear and tear because they are very heavy and made of a much heavier and more durable metal. The rubber bushings on the OEM brace give them enough play to be ok. Lighter test pipes though.. well that could be a whole different story.

The brace is just there because the OEM cats are pretty heavy.. it helps support their weight.. it's as simple as that. The brace is not there to save your exhaust from the engine flexing around. The ART Pipes weigh like half as much, so the headers and exhaust system should be able to bear the weight themselves, without the help of the OEM mounting bracket.

Considering the relatively rare availability of the VHR ART Pipes, it's hard to tell. Most test pipes and HFCs have a mount tab for the brace, and most shops do reinstall it. I believe overtime you can break a flange without the brace if you don't have an exhaust with a flex section - it is there for a reason beyond just supporting OEM components. It's to lessen flex and tilt and the wear it causes in general. Invidias are having issues more rapidly due to their design (again: flex sections), but I wouldn't rule out other exhausts eventually developing issues as a result of this either, even though it will take some miles, which will also vary on driving style.

When I unmodded my 350Z, my shop forgot to install the brace back on. They simply told me to take it easy and avoid frequent burst of throttle, otherwise I stood a chance at hurting the cats or y-pipe without the brace.

Not sure about Invidia being a knock off brand...their exhaust doesn't look or sound like any other out there. They make a pretty quality product. That said, I'll reiterate my point about another member who had to warranty two flex sections from his Invidia because of his test pipes (which are even lighter than ART Pipes) and it stopped tearing once the brace was put back on.

Don't think weight plays that much of a role. It's bracing to limit flex that's most important.

Bad idea... Any hfc or test pipe with the stock mounting tabs always break or crack.. Do a search on how many berks crack with the tabs. Alot including my old ones.. How many crack with no tab.. Virtually none.. Do a search and u shall see..

What? That sounds backwards. On the 350Z Berks were cracking because they didn't have tabs...then Berk added them and cracking issues stopped for good. I can't imagine the opposite being true for the 370Z.

Can you link me to the threads? Searching provides way too many irrelevant results.

Exhausts breaking is a defect of the exhaust. And from my experience, a brace on the test pipe is more likely to cause cracking and failure than not having one. So we don't include for that reason.

I certainly don't recommend it.

The tabs you refer to are bolted to the transmission, which is bolted to the engine, which is free floating on the engine mounts, so the entire assembly moves all the same. The bracket doesn't stop the engine movement. It only reduces flexure of the test pipes or stock cats between the engine and the bracket. But then all the flexure force or torque is then moved from the bracket on back.

In the case of the stock cats, they are heavy and large in diameter and have a high coefficient of rigidity. IE they have no tolerance for flexure because any flexure will be localized to the inlet flange weld point. This obviously is a bad place to have any flexing.

In the case of ART pipes or regular test pipes, the ENTIRE PIPE IS A FLEXURE. It is better to allow the whole pipe flex because there are no stress risers in it. The pipe can easily flex over its entire length and have no problem doing it for a long period of time with a high number of cycles.

Add a bracket to the mix and all that flexure force will be localized and focused right at the bracket weld joint... Stress risers are not a good thing.

If any exhaust has flex sections breaking, it is a result of weak flex sections.

Hmmm, alright Tony, I will take your word for it.

I won't cut and weld the tabs from the OEM cats to the ART Pipes. Hoping for the best this Saturday.

That sounds reasonable to me.

By the same logic, if anyone chooses to fab up a mount regardless, it sounds like it needs to allow a little rotation because the pipe gauge isn't as heavy as OEM. A weld would struggle at that task because it doesn't give much. Something like an engine mount or exhaust hanger would be a better model.

Personally, I wouldn't bother. It sounds like they've given it thought and intentionally omitted the mount, so it's not like this was a clear oversight or blunder.

The 4th production run of the new design just came of QC this morning so the entire back order list will be finished today and we will ship them out immediately.

If you were on the waiting list feel free to contact us 661 298-7555 or via email sales@motordyneengineering.com

ART pipes are now live on our website.:tup:

Emailed :)

So if I put my order in today, how long until they ship? Are they actually in stock for those not on any list so far?

We have them in stock now. It depends on how quickly we are able to pack and ship.
I estimate ~2 days to ship.

Tony: someone at Z1 mentioned to me that the hissing sound I am hearing after installing the ART pipes is actually coming from the Y-pipe of my nismo exhaust rather than the ART pipes themselves. Do you know if this is true? What exactly is making this sound? It's not too audible outside of the car, but it drowns out some of the exhaust note between 3-5k rpms. I'm wondering whether this y-pipe is too restrictive or something. Or perhaps it really is just a VQ thing that I need to get used to. Any comments?

I havn't personally heard that combination so its hard for me to say, but if Z1 heard it, they are better qualified to say what it is.

Apparently the hissing is very common on this engine. I'll find out soon enough what the issue is because I have a whole lot of exhaust dyno tuning coming up for the Motordyne exhaust R&D.

I highly doubt it's the Y pipe as everyone has hiss with these VQ's after removing stock cats. I have the HKS dual and theres no Y pipe, but a lot of hiss.

They didn't actually hear it. They are just of the opinion that test pipes sometimes cause the y-pipe to make that hissing noise. I'll be interested to hear your testing results.

For those of you with an aftermarket CBE and ART pipes: do you get a hissing noise under heavy throttle from about 3-5k?

the VQ's have the hiss. Some exhausts make it louder/quieter depending on the design. The reason the ART pipes made it louder is due to the increased flow. But if you did regular test pipes, resonator, HFC you would hear the hiss as well. So yeah unfortunately it is a exhaust thing more than the HFC/TP but the HFC/TP tend to get the blame as most people notice it only after installing those.

I have an aftermarket Y-Pipe exhaust and have very minimal hiss with the ART Pipes. With test pipes the hiss was MUCH louder. Now I barely notice the hiss, but with test pipes it was very noticeable.

It is a product of the VQ, so there isn't really a way around it that I know of. Obviously restrictive cats basically eliminate it because they disrupt the air stream so much. I don't have any personal experience with true dual exhausts but I have a feeling that they could possibly minimize it some, but who knows. I will say that the hiss definitely comes from the Y-Pipe. I have gotten under my car and listened to someone rev it, so I know this is the case. But, if you had a true dual, it could still come from the same area.. so who knows if it's a y-pipe thing or it's just a VQ thing.