I actually looked under the car and it appears as if there's close to an inch of clearance above the cross member but I could be wrong. And it sounds like it's coming from the passenger side. Im going to go back to the dealer who installed it tomorrow to have them trouble shoot it. To my knowledge they didn't take the "ark precautions" when installing it (jacking up the x pipe prior to tightening bolts). Hopefully that helps. Maybe there's something rattling on the passenger side by the canisters idk. Yesterday it wasn't rattling at idle on cold start or under load but it is now (ie it's getting worse). So maye that points to a loose bolt or attachment?

Also, beyond the SOUND of the rattling there's an actual FEEL as well. You can feel a vibration in the cabin and through the gearbox. This leads me to believe there exists some degree of metal on metal contact that can hopefully be fixed with a proper re-install.

THANK U everyone for all your input. It's really frustrating when this stuff happens.

Man I feel for you, excited about getting the mod installed then to be faced with a pile of crap and un satisfactory performance.
Think you are doing the right thing in taking it back, the should really have test drove it with you to ensure you were happy. GL dude. Hope you are satisifed in the end and can enjoy it.

the VQ typically has hiss on decel, mine got pretty prominent after LTH's and the Meisterschaft, but hiss on acceleration shouldn't be all that prominent.

Thanks bro. With my wrx I had a lot of one off parts that took a lot of testing and tuning to work properly and since it was my daily driver it was also quite frustrating making friends with the tow truck driver after some mods led to the car being un-drivable. It is frustrating but the fact that the rattling is getting worse and can actually be felt in the cabin is actually somewhat re-assuring because it leads me to believe that there is metal on metal contact that can be fixed with a proper re-install as opposed to some mysterious horrific rattling sounding resonance produced by the combination of the GTM test pipe and ark exhaust, though I can't completely rule that out.

But even a passenger felt and heard the rattling on the car without me saying anything about the car. All she said was "what's that rattling noise". So I'm hoping we can make some headway by getting it on the lift and re-installing the system with propping up the x pipe prior to tightening the bolts.

You know a inch isn't much. And under acceleration the exhaust will flex some. I've had this before. If this is the case wrapping exhaust wrap around that portion of the pipe is the best fix.

Yea its not the hissing and whistling I'm concerned about. I know that happens with headers and test pipes. It's the very loud rattling that I can hear and feel that's now prominent on cold start, decel, and under load most noticeable around 2500-3000. It rattles so much it feels like the canisters are being dragged along the pavement.

I'd love to hear a clip of your setup. I can't imagine how loud it is. Even without the LTH that CBE is mean as hell

Good to know. I do remember reading some posts from members with the ARK GRIP who had bad rattling when not installing it "properly" (jacking up the x pipe prior to tightening all the bolts). I doubt they have exhaust wrap at the dealer but I'll keep that in mind if a re-install doesn't fix the rattling.

If it's the crossbar underneath, at least on my G37 sedan, it's an unnecessary part. I took mine off. No more rattling... :)

But definitely have them do a once over to make sure everything is on there correctly!

Wont removing it lead to less chassis rigidity and poorer handling? Even still, I'm sure ARK designed the exhaust to fit properly so the installer should make that happen

Sounds like a bad install with a leak to me.

Its the Ark and test pipe combo . This has been hashed many times on other forums.

So you think the rattling isn't mechanical (metal to metal)? If this is what's happened with test pipes and the ARK I'll just re-install the stock cats. Do you have any links to the other forum posts? It really sounds like there's a metal on metal rattle. It vibrates the whole cabin and you can hear it at idle now.

If this has been documented with the combination of ark + test pipes I'll have the dealer relace the stock cats. Any help is appreciated as I'm going back first thing tomorrow to have this rectified. Thanks everyone in advance. All the advice is appreciated!!!

BLM, as i told you, its a leak. The dealership will not install properly, they just want your money, never let dealership maintain your car. I do my own oil change since day one.

When i installed FI exhaust and TP there was a stupid sound that makes the car sound like cheap, i took it back and told the garage to re installed everything and told them to use silicon everywhere

took the car back home and the sound was day and night different,

hope this message cheers you up.

Most definitely. I'll insist they do a re-install with propping up the x pipe prior to tightening the bolts and adding a silicon sealant between all the connections.

sounds like a plan, but they should do it for free, dont pay anything, maybe 10$ for silicon but no more! its there fault, they didnt pay attention when they were installing your exhaust.