Virgule

When I first got my Hooker AeroChambers installed 2 months ago, the initial level of drone was slightly disappointing. Although the drone was present at around 1800 RPM, it tended to fall off sharply, and at 2000 RPM, was barely even noticeable.

Lately though, I haven't noticed ANY drone, which leads me to this contentious conclusion - chambered mufflers perhaps DO need a break-in period, before they settle down. Now the break-in process itself is unknown, butI think the constant heat and pressure alters theinternalsbaffles just enough to perhaps"soften" the resonance, like breaking in a new pair of Florsheims.

Or, I could just be going deaf. LOL

swata

I know the flows I had on my old T/A sounded better after driving for a few months. They got deeper, but the drone was still there.

With my 06 GT I still have the stock exhaust and they do sound a little better with a few thousand on them.

I would say from experience that they do have a "break in period".

my77stang

i imagine its something to do with the layer of soot that builds up in there probably changes the reflecting properties of the metal inside.

could it be??

xbone

We used to call it "blowing them out" which was when they actually put fiberglass in them that would come outover time. Not so sure what would cause them to change now except metal expansion and contraction opening up the baffles.