Removed 3rd cat today... unwelcomed rasp

[askoncemore]

Replaced the 3rd cat today with a 2 1/2" X-pipe.

Patrial throttle I get an annoying rasp. No rasp on normal driving or full throttle.
I had a slight rasp prior to the X-pipe install.

Is this due to the flexible coupling on the downpipes?

My setup:
3" non catted downpipes
2 1/2" X-pipe
Stock resonater
Stock mufflers
Meth
Modified intake
Tune

 

[ZSHO]

Is everything tight by the Flange pipe? Check for worn out insulators on the pipe which can exhibit a rattle or vibration and check for any play in that intermediate area especially having 3"DP without cat's preferably the passenger side ....think its #9 on the Diagram.  Z      When did your issues start?          http://www.levittownfordoemparts.com/auto-parts/2013/ford/flex/limited-trim/3-5l-v6-gas-engine/exhaust-system-cat/exhaust-components-scat

 

[SHOdded]

Catless downpipes (even some highflow catted downpipes) are known to expose the buzz/rasp of the engine.  No 3rd cat/X-pipe will only help propagate the issue.