Why does a new cat-back system get quieter after a week or so???
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Joined: Nov 2001
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From: I-L-L-I-N-O-I-S
Why does a new cat-back system get quieter after a week or so??? I have honestly never been able to figure this out...And don't tell me it's because I got "used" to the sound; because I've been used to loud cars forever and it has happened every time I've done this! Anyway, I just had a GMMG put on my LT1 and the thing was loud as heck (idle, low rpms, whereever). The rumble/drone was particularly loud in the car around town. Now, after putting a few hundred miles on the system, the drone is all but gone and the exhaust just seems so much quieter inside the car at any rpm (I swear it's even quieter at idle!). Still sounds mean as he!! when I rev it up, but I guess I'm just disappointed because of how much quieter it seems down low or around town...I experienced the same exact thing when I put the GMMG on my two LS1's and even the SLP Loudmouth on my first LS1... 
I know everyone usually says you got "used" to the sound, but the system has honestly mellowed out some and I don't know why? I'm sure carbon build-up in the pipes might be a cause, but it's obviously way too soon for something like that to occur...Anyone feel the same way or at least know why this happens?
I know everyone usually says you got "used" to the sound, but the system has honestly mellowed out some and I don't know why? I'm sure carbon build-up in the pipes might be a cause, but it's obviously way too soon for something like that to occur...Anyone feel the same way or at least know why this happens?
Launching!
Joined: Aug 2004
Posts: 297
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From: Memphis, TN
Personally I have had quite the opposite experience with the installation of a new exhaust systems.
It always seems to be louder after about a week from when it is installed...
So I have no answers for your question...
It always seems to be louder after about a week from when it is installed...
So I have no answers for your question...
!LS1 11 Second Club
Joined: Apr 2003
Posts: 7,133
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From: Miami
You honestly get used to it. I remember driving away from the exhaust shop with a new set of tru duals dumped at the axle. It felt like I was driving away in an all-out track car. A week later, I thought my car wasn't loud enough. It took people telling me that my car was the loudest car they'd ever heard for me to realize exactly how loud my car was.
One day I forgot my wallet inside the house and I ran inside with the car idling. When I went inside, I realized that the entire house was thumping along with my cam and I asked my wife "is this what it sounds like every day when I leave?!!!" And thought to myself "my poor neigboors!".
You get used to it.
One day I forgot my wallet inside the house and I ran inside with the car idling. When I went inside, I realized that the entire house was thumping along with my cam and I asked my wife "is this what it sounds like every day when I leave?!!!" And thought to myself "my poor neigboors!".
You get used to it.
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yeah I bet you are just getting use to it. My magnaflow on the other hand seems to get louder everytime I crank the car. But then again I only drive my SS on weekends and sunny days
Joined: Nov 2001
Posts: 34,646
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From: Schiller Park, ILL Member: #317
Originally Posted by SteelBallz
Personally I have had quite the opposite experience with the installation of a new exhaust systems.
It always seems to be louder after about a week from when it is installed...
So I have no answers for your question...
It always seems to be louder after about a week from when it is installed...
So I have no answers for your question...
BTW 2000LS1Z28, long time no talk.
I always that that this was due to carbon building up on the walls of the exhaust tubing. My car was unbearable when I switched to LTs and ORY for about a few days. Who knows... maybe I got used to the noise or maybe it did quiet down some. However quite the opposite happened when I put a Borla XR-1 in my I-pipe to cure the rasp of my Borla cat-back. I thought that it was very quiet at first , now my ears tell me that it got louder after a few hundred miles..... which ia good thing if you ask me. If I wanted a quiet car I'd be driving an Accord or some other POS.
Magnaflow and borlas and any other straight through muffler will get LOUDER over time and continue to do so until they are no good any more ( a long time ) a chambered muffler such as flowmaster will get louder and then stay that loud always. This is because the metal baffles inside can only move so much as they are stopped by the casing. So my two cents is you got used to it as illustrated by SouthFL.02.SS.
