Poe408

i've installed cat-back exhausts on my cars a few times and they've always gotten louder after being driven on for a while. when they're brand new, they seem to be a bit quieter. why is that? what changes?

BluestickG

iTrader: (5)

Most of the time its because the muffler uses packing. Which is kind of like fiberglass insulation you put in a house. The packing is what muffles the sound, but after awhile the packing can be blown out or gets dirty and old. This will make your decibel to go up.

rAiN

iTrader: (5)

could be the gasket blown or burned out.

dimsler

iTrader: (7)

Packed mufflers if they are good quality usually get quieter from the carbon build up, especially if you have test pipes. Chambered mufflers if they are cheap get louder as the chambers rust out.

MistAminER112

to be honest, I think mine got quieter but also deeper, prolly has to do with the system 'settling in' and the gaskets sealing off? Not an expert, maybe Tony@FastIntentions could answer that for you, he's an exhaust expert

InspiredMan

packing is burning off.