Noise on deceleration and taking off in 1st
 

I recently noticed a really strange loud sound coming from the passenger side of my BRZ and have no clue what it could be and figured I check with the wise men of this forum. The noise is most noticeable when taking off in first in the low rpms, when taking my foot off the gas, and sometimes when I first start the car up. I have a gruppe S header and the rest of the exhaust is stock. Also have a oft on stage 2 E85 if that means anything. Here’s a link to a video of the sound of that helps at all. Thanks in advance

https://youtu.be/vpYLf6cyK4c

Regarding passenger side .. isn't that the place where soundtube is passed in? Plug it off for experiment sake using "free" cap from lighter 12V socket in glovebox.

Already did that. Thank you though

Is the sound related to engine speed?

Related to car speed?

Does it make that sound if the car is not moving?

Come back.

It seems worse in lower rpms when taking off in first and is only audible at low speeds. The sound is there when idleing but it is much quieter.

Exhaust rub?

Check that your front pipe bolt hasn't rattled itself loose. Mine did that after I swapped the mounts and the noise was most apparent at low rpms and was coming from the door area, driver or passenger.

You were right, thank you so much!