Remove Cats... Sound?
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From: In a van down by the river, Missouri
What cat-back do you have, stock? The only catback without cats that i consider raspy is the slp loudmouth and it doesnt just sound raspy it sounds like ***!
Take the cats off, you will like the sound.
Take the cats off, you will like the sound.
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From: Central Indiana Honors: 4th grade spelling bee contestant
Originally Posted by SScottie
What cat-back do you have, stock? The only catback without cats that i consider raspy is the slp loudmouth and it doesnt just sound raspy it sounds like ***!
Take the cats off, you will like the sound.
Take the cats off, you will like the sound.
If you don't want it loud, then I'd leave the cats on.
I gutted mine. I have the SLP CME exhaust ("factory" SS option)
and the idle note got a little louder but it's still mellow and just
healthier sounding. Not an attention getter, just a little looser
in the throat. A little more boomy at 2000-2500RPM. A little
louder up top I guess. But nothing like when the cutout is open.
Now, if you had something like a Loudmouth, then the cats are
your only remaining muffling and taking them out, you're letting
a lot of high frequency nastiness right out the pipe ("rasp").
A very low restriction aftermarket exhaust, probably close in
degree. The more restrictive factory, base exhaust, probably
even less noticeable than mine.
I think the best way, if you want to stay stock configuration,
is a pair of the Mufflex or similar offroad tubes. Those should
boom less than gutted cats (which become then just resonators)
and fit right up. Damn expensive for being just two feet of pipe
with flanges on the end, though. You should be able to get a
used set of cats and bust the bricks out, for near nothing. Even
over there. Then swap those on and keep your (presumbly working)
ones for later, in case you or the emissions police decide you need
to go back.
and the idle note got a little louder but it's still mellow and just
healthier sounding. Not an attention getter, just a little looser
in the throat. A little more boomy at 2000-2500RPM. A little
louder up top I guess. But nothing like when the cutout is open.
Now, if you had something like a Loudmouth, then the cats are
your only remaining muffling and taking them out, you're letting
a lot of high frequency nastiness right out the pipe ("rasp").
A very low restriction aftermarket exhaust, probably close in
degree. The more restrictive factory, base exhaust, probably
even less noticeable than mine.
I think the best way, if you want to stay stock configuration,
is a pair of the Mufflex or similar offroad tubes. Those should
boom less than gutted cats (which become then just resonators)
and fit right up. Damn expensive for being just two feet of pipe
with flanges on the end, though. You should be able to get a
used set of cats and bust the bricks out, for near nothing. Even
over there. Then swap those on and keep your (presumbly working)
ones for later, in case you or the emissions police decide you need
to go back.
LOUD! I have macs/oryp and ultraflow dynomax. I will be putting on some magnaflow cats this week. I have an a4 with a 3200 converter and it is real raspy 2000-2800 which is where my car stays when just easing around town. It is quiet when the converter locks up and sounds like a race car when I floor it!
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From: Acworth, GA
Originally Posted by y2k_ta
It's defiinitely louder. I had the SLP Loudmouth on my 'bird. After removing my cats and installing longtube headers, it sounded good at idle but was really raspy upon acceleration. I loved how loud it was, but didn't care for the rasp at all. I ended up doing the "Dynomouth" mod and it cured the rasp, but left the volume basically the same. Now it sounds great.
If you don't want it loud, then I'd leave the cats on.
If you don't want it loud, then I'd leave the cats on.
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From: Tranås, Sweden
Originally Posted by SScottie
What cat-back do you have, stock? The only catback without cats that i consider raspy is the slp loudmouth and it doesnt just sound raspy it sounds like ***!
Take the cats off, you will like the sound.
Take the cats off, you will like the sound.
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Joined: Sep 2003
Posts: 617
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From: South East PA
your car will be alot louder, but it will get pretty raspy depending on the cat back or true dual system you are running. I dont mind mine but you may not like how it sounds, your best best is to go to a site like ls1sounds.com and see what the difference in the exhuaast note is or listen to someone elses
Originally Posted by atljcope03
What is the Dynomouth mod? I took my cats off, love the sound and hate the rasp.
Take the cats off and run it with a loudmouth. It's quiet as a mouse 
In all seriousness, I like loud cars and a little rasp or interior drone doesn't bother me. If you take the cats off get True Duals, catbacks sound like **** without cats.
In all seriousness, I like loud cars and a little rasp or interior drone doesn't bother me. If you take the cats off get True Duals, catbacks sound like **** without cats. 
Is the rasp coming from the resonator itself, or the the y-pipe junction? If you had a flo merge collector, would you still have that rasp? Maybe the resonator amplifies the rasp once the cats are gone?