View Single Post
      10-18-2020, 10:32 PM   #4
TopJimmy
Major General
TopJimmy's Avatar
United_States
5459
Rep
5,152
Posts

Drives: 2023 M3 Comp xDrive
Join Date: Jul 2019
Location: Chester County, PA

iTrader: (5)

Quote:
Originally Posted by E92TiAg335i View Post
I think maybe it's just the lack of the flex joint?
My ER sport cats are pretty big and don't have a flex joint. I had no vibration from them with my factory exhaust. Maybe it's the pulses going down the open pipes that you feel? My vibration started after I installed my AA Signature exhaust kit. Catted DPs with a 3.5in school-bus exhaust really makes some noise.

To check for rattles or vibrations I jacked the car and put a stack of 3 cut 2x8 wood blocks under the tires, then lowered onto the blocks. Start the car. Go lay next to the passenger side and use your sneaker to push on the (hot) pipes. If a vibration starts/stops you found a spot to check better. If no footwork changes the sounds then there's nothing to fix. Sometimes a few chips of a wine cork can be wedged under a vibrating heat shield to quiet things down. Best to check when cold, things rattle more.
__________________
'18 F80 Base 6MT | '19 F82 Exec DCT | '18 F82 Comp Exec DCT | '23 G80cx
Appreciate 1