Can I ask what is your setup?
NP....I've ran it two different ways.
ARH LTH's
ARH Off Road H
2013 GT OTA Pipes
Super Snake Cat Back
Stock Manifolds
Stock Mid Pipe
2013 GT OTA pipes
Super Snake Catback
The GT OTA's have resonators incorporated into the design.
Exhaust still has a great growl. No rasp and no drone.
I also have 3:73 gears, maybe, my RPM is higher than 3:31's when cruising and that may help as well. IDK
You will notice a dent in the L/H resonator. That's like that from ford. No idea why
Pic taken before header install
@1 Alibi 2 runs the Kooks Headers version with Hi Flow mid Pipe and 13 OTA's