all muffler and exhaust questions go here!!!!!!
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Joined: Jul 2011
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Year: 1998
Model: Cherokee
Engine: 4.0L
Stock exhaust is 2.25 right?
Would it be better just to get a 2.25 muffler to bolt on to the cat or get a larger size and get a pipe that goes from 2.25 to 2.5? I'm not planning on going 2.5 from the header back because the cat will still restrict it.
Actually I can get a muffler with a 2.25 inlet and a 2.5outlet...
Would it be better just to get a 2.25 muffler to bolt on to the cat or get a larger size and get a pipe that goes from 2.25 to 2.5? I'm not planning on going 2.5 from the header back because the cat will still restrict it.
Actually I can get a muffler with a 2.25 inlet and a 2.5outlet...
Effects of going to 2.5" pipe may be partially dependent on muffler design (size and baffling) , exhaust headers, intake ... etc.
I haven't worked on the exhaust for a several years ... after going over my notes, remembered looking at mandrel bent, Mopar Cat-back 2.5" systems ... for maximum performance were used with Mopar performance headers, - (p524997 - 96-98, p4876918 - 86-91)
P4876359 Cat-Back performance exhaust ... 1986-96 XJ
P4876089 Cat-Back performance exhaust ... 1997-98 XJ
http://www.summitracing.com/parts/DCC-4876089/
Last edited by Anony; Oct 16, 2011 at 06:57 AM.
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From: 92392
Model: Cherokee
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From: Las Vegas
Year: 1999
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I don't think any aftermarket header offers a 2.5" collector..most have a 2.25"..The walker evans crossover/s-pipe/downpipe...same ****...is trash! Its 2.25" crush bent...Our stock is 2.25" mandrel bent...with a dent lol. 
The walker evans won't be an improvement at all. I think its actually a step backwards! You need to get a custom downpipe made! 2.5" mandrel bent! Anyway can make it for ya!
The walker evans won't be an improvement at all. I think its actually a step backwards! You need to get a custom downpipe made! 2.5" mandrel bent! Anyway can make it for ya!
So this is normal?
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that was my exact reaction to seeing that dent in my pipe...I thought WTF?? I bought a walker down pipe. Its setting in my garage waiting on my APN header. Its hard to say if the Walker pipe is going to flow better or not. But I do think the stock dent is more restrictive than the crush bends on my new pipe.
Registered Users
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From: 92392
Model: Cherokee
Registered Users
Joined: Jul 2011
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From: 92392
Model: Cherokee
CF Veteran
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From: Milwaukee, WI
Year: 1987
Engine: Check
CF Veteran
Joined: Sep 2010
Posts: 21,168
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From: Milwaukee, WI
Year: 1987
Engine: Check
That's also not a Renix header. The Renix o2 is in the manifold, not the down pipe.
