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Unread 05-11-2014, 11:47 PM   #1
davidtownsend
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2006 WK 
 
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So I have a universal cat on it now but am wanting to change it due to my plenum was bad. I had to rig my cat and muffler with clamps to get it past expectation in MD. Now that the metal is all bent i'm going to get either a 3" or 2.5" tail pipe from iron rock. I also have a knock off magnaflow muffler and want to get a real one since the clamps bent the tubing. I'm hoping in the near future I am going to get headers to finish my exhaust. My question to you is what cat and muffler should I get? I want to keep it all magnaflow unless something out performs them in performance. There are a lot of models for both of these items. Another question is what size tail pipe should I get? I drive mainly on highways and interstates with minimal wheeling. I have a 5.2 with a Durango hat, ported kegger, and CAI. Thanks for the help everyone!

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Unread 05-12-2014, 06:15 AM   #2
AlphaLorde
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Even with simple bolt ons 3" piping is a little big for a 5.2, its even a little big for a 5.9.

I'd run 2.5" from the y pipe back. If you can afford it have the exhaust shop take out the crushed pipe by the oil filter and pass. upper CA. Its been proven time and time again that is good for about 10 ponies and make it a smoother running rig.

Here is a list of good cats for our jeeps
http://www.cherokeeforum.com/f10/my-...verters-96369/
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Unread 05-12-2014, 08:52 AM   #3
davidtownsend
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Quote:
Originally Posted by AlphaLorde View Post
Even with simple bolt ons 3" piping is a little big for a 5.2, its even a little big for a 5.9.

I'd run 2.5" from the y pipe back. If you can afford it have the exhaust shop take out the crushed pipe by the oil filter and pass. upper CA. Its been proven time and time again that is good for about 10 ponies and make it a smoother running rig.

Here is a list of good cats for our jeeps
http://www.cherokeeforum.com/f10/my-...verters-96369/
Thanks man. I did replace my entire y pipe. So I don't know if it is still a problem.
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Unread 05-13-2014, 04:39 PM   #4
davidtownsend
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What's the difference between the 300 and 400 hole cats?
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Unread 05-13-2014, 04:48 PM   #5
firsttimeZJ13
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My guess would be more flow with 400 holes. Anyone know why they crushed the pipes anyways??
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Unread 05-13-2014, 11:04 PM   #6
davidtownsend
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What side of the stock muffler is offset? And both inlets/outlets are 2.5 right?
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Unread 05-14-2014, 01:07 AM   #7
Kolak
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They crushed the pipe because of assembly line installation ease.

The number of holes is not the only parameter that determines flow. You have to also consider the area of the substrate as well as the frontal area of the converter case, the shape of the case, and the transition from the pipe nipples to the body.

Magnaflow does an excellent job at maximizing converter flow. If you'd like any exhaust information, PM me here on the forum or email me at kolak@aol.com

Jeepforum members get 10% off my Kolak Exhaust by the way.

Quote:
Originally Posted by firsttimeZJ13 View Post
My guess would be more flow with 400 holes. Anyone know why they crushed the pipes anyways??
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Unread 05-14-2014, 02:22 AM   #8
firsttimeZJ13
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Well that makes all the sense in the world. I do need to replace my y pipe some day.

David, my offset was towards the middle of the jeep if I remember. I cut it off the weekend I brought it home due to an entire corner missing from it.
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Unread 05-15-2014, 06:16 PM   #9
davidtownsend
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Can anyone post a pic of the stock muffler?
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Unread 05-27-2014, 12:56 AM   #10
davidtownsend
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This might be a long shot but has anyone ran a 200 cell metallic cat? If so how does it run?
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