Chasing down exhaust leak with E370 + ART

MaQG37

Hello, I recently bought a new E370 shockwave system + V3 ART Pipe system for my g37 sedan. The first 3 days, the exhaust note was perfect, only hissing on the decel which I was totally fine with. After about 3 days, I started hearing hissing on full throttle and medium throttle. I have taken it apart myself personally 3 times to inspect for leaks. So far, the only indication of a leak I could find is at the Y pipe to ART pipe merge where there was exhaust soot. The bottom of the flange is not sitting flat against the ART pipes. I tried using Vibrant gaskets + ultra copper RTV and the noise hasn't gotten better. I keep getting feedback that this is a byproduct of having ART pipes. But, this is pretty loud that it pretty much overpowers alot of the exhaust note when I have the windows down. I have spoken with Tony from motordyne a few times and he's been trying to help me narrow down a leak. But, also mentioned that the noise could be normal.

I removed the art pipes, no signs of soot on the flange. The v-bands are tight. I had the car on a lift while a buddy felt for leak with his hand and a stethoscope and could not find anything significant.

After I took this video, it's very evident that this is just not the normal test pipe hissing. It really lacks the signature E370 exhaust note especially with ART Pipes. Does anyone have any suggestions on what else I could try? Motordyne is shipping me new gaskets and my next attempt willl be to loosen the whole exhaust system. Start from the Y pipe and tighten everything all the way back to the axleback.

https://youtu.be/fuymiXC0hyU

abm89

Based on the design of the shockwave exhaust, I would bet your problem lies with the Test pipes and what they are in contact with. I think you're already on the right route.

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