I was actually thinking of possibly getting exhaust heat wrap if it came down to it. Wrapping the art pipe would prevent it making noise if it touched anything. Anyone ever try this route?

 

I wouldn't check the ART pipes, but maybe the Y-pipe flanges making contact. My Y-pipe flanges which connect to the test pipes make contact to the underbody, creating violent rattles and vibrations heard from long distances --extremely embarrasing.

Usually if you have the cat brace installed correctly, the movement of the exhaust is transferred downrange like a whip, to the Y-pipes--possible the flex pipes hitting the under-body as well.

 

I'll take a closer look at that too. I may try to play with the brace again.
Thanks

 

ever figure it out?

 

I thought I did but then it happened again at the end of the day. Two days ago I noticed the U-brace was actually loose on the driver side, connecting to the ART pipe, and that there was some play with it. So i tightened it up and everything else looked fine down there. Everything has adequate clearance. O2 sensors are tight and not making the noise. The car drove in the heat all day yesterday with no issues until later in the day. My only assumption is maybe the nut loosened itself again?

 

possible..... check again and if that is the case throw some locktite on it

 

Sorry to renew this thread but I still havn't fixed the issue and it is driving me insane.
The other day as I was checking the pipes, I didn't notice any scrapes or dings around the art pipes. I did however notice a few scrapes in the metal around my y-pipe braided flex joint. The braided flex joint is currently leaking and I'm wondering if that could somehow be the issue.
Could the disruption of airflow caused by the leak make the y-pipe move?
If it isn't that then I'm completely out of ideas. Everything else looks solid down there.

 

I had two sets of ARTs in Phoenix in the summer (over 110 at all times)

None of this happened.