Purchased this AFE also after 20K worth of the AFE muffler delete pipe. 5.3 never sounded so good, drone at speed insane.
Took to my local muffler shop to have flapper valve (they claim it is an unnecessary valve to assist with engine warm-up) removed.
Did the install with additional pipe (the piece that comes with the muffler is too short to remove flapper).
Did a very professional install, no more "Bark" at cold start (neighbor appreciated) and no drone while driving, but still sound respectful. Thinking of doing an
lbz up pipe EGR delete next to keep the airflow smooth and reduce future clogging issues.
