Author Topic: High Flow Catalytic Converters  (Read 3436 times)

Offline bladerunner

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High Flow Catalytic Converters
« on: August 09, 2011, 07:34:31 PM »
So I am looking at installing cats this week and I am in the process of choosing what I want. I have dual Flowmasters and I like the current sound; deep and throaty with a little rasp.  Maine has no restrictions on high flow cats so I will definitely go that route.  Anybody have any recommendations that won't restrict performance or sound? Will any high flow cat work or should I look at particular brands?
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Offline zieg85

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Re: High Flow Catalytic Converters
« Reply #1 on: August 09, 2011, 08:19:19 PM »
Any cats will soften the sound somewhat just by the nature of them.
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Offline bladerunner

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Re: High Flow Catalytic Converters
« Reply #2 on: August 09, 2011, 08:48:55 PM »
I suppose that is what I am really asking. Some guys say the sound reduction is more drastic and others say it is only slight.  My experience is that it is a slight change, maybe a little less raspy. I am just curious what others think. Thanks!
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Online Da67goatman

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Re: High Flow Catalytic Converters
« Reply #3 on: August 09, 2011, 09:01:48 PM »
Compared to a stock cat, a high flow is louder and more crisp, but compared to no cat, its softer and more blended.  Now we're only talking a couple decibels but it is a difference.
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Offline 1979C20

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Re: High Flow Catalytic Converters
« Reply #4 on: August 10, 2011, 01:57:51 AM »
Why not hollow a cat converter out and run a tube through the middle so a "cat" is installed, but not hindering the sound? I know a bunch of people around town that do it.
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Offline Irish_Alley

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Re: High Flow Catalytic Converters
« Reply #5 on: August 10, 2011, 02:14:08 AM »
i would just punch one out. i dont see the point in a tube inside of it maybe for mother air flow but its not needed i have heard of a company that sells the shell you can weld that onto a strait pipe so it looks like a cat

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Offline ToddN

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Re: High Flow Catalytic Converters
« Reply #6 on: August 10, 2011, 11:39:40 AM »
I use stainless clamps to run true duel to two cats to two turbo mufflers...after inspection I take off the cats and run two 8" glasspacks right from the headers and they dump out just behind the cab. The whole setup takes less than an hour to switch out.
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Offline ToddN

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Re: High Flow Catalytic Converters
« Reply #7 on: August 10, 2011, 11:40:06 AM »
Oh....and I am also from Maine.
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Offline Psycho71

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Re: High Flow Catalytic Converters
« Reply #8 on: August 11, 2011, 01:29:08 AM »
http://www.frozenboost.com/index.php?cPath=210&osCsid=87b8b8d4882f7395e304a9f3530288b7

I put these on my burb, they passed the visual inspection no problem.
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Offline bladerunner

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Re: High Flow Catalytic Converters
« Reply #9 on: August 13, 2011, 02:42:44 PM »
In Maine, a visual inspection is all they do.
85 K10 Shortbed
94 Impala SS