Custom Exhaust - Help Please!
Thread Starter
JK Enthusiast
Joined: Sep 2007
Posts: 171
Likes: 0
From: Conifer, CO
Custom Exhaust - Help Please!
Ok, I want to do a custom exhaust system. I've listened to the sound clips in that thread and I like the Magnaflow the best. I want to locate the muffler in front of the evap canister between the frame rail and the drive shaft the way I've seen some other do. Like this:
https://www.jk-forum.com/forums/modified-jk-tech-2/new-cat-back-installed-73800/
I will reuse the stock heat shield. However, I want to get a single pipe in, dual pipe out muffler, like this:
magnaflow.com/02product/shopexd.asp?zone=main&id=7965[/url]
Then I'll have a muffler shop fab two pipes from the muffler to rear over the axel the way the stock pipe runs. Some questions and things I don't understand:
1. What is the difference between a "cat-back" system, and just buying a new muffler? I read that a cat-back is "everything between you catalytic converter and your tailpipe". Isn't that just some exhaust pipe and a muffler? Why do "cat-back" systems cost so much more in the jeep parts catalogs than just buying a new muffler? If I just buy a magnaflow muffler and bring it to a shop to get the tubing bent and welded, am I screwing up my emissions system? I can't have this thing fail emissions next time I am due to get tested.
2. Has anybody ever considered cutting two holes in their aftermarket bumper to run the exhaust tips out? Might look a little funny, but wouldn't that protect them from being crushed? ( I haven't spent much time laying under the jeep to see if you can even route the pipes this way)
3. Round vs. oval mufflers, what's the difference?
Thanks!
https://www.jk-forum.com/forums/modified-jk-tech-2/new-cat-back-installed-73800/
I will reuse the stock heat shield. However, I want to get a single pipe in, dual pipe out muffler, like this:
magnaflow.com/02product/shopexd.asp?zone=main&id=7965[/url]
Then I'll have a muffler shop fab two pipes from the muffler to rear over the axel the way the stock pipe runs. Some questions and things I don't understand:
1. What is the difference between a "cat-back" system, and just buying a new muffler? I read that a cat-back is "everything between you catalytic converter and your tailpipe". Isn't that just some exhaust pipe and a muffler? Why do "cat-back" systems cost so much more in the jeep parts catalogs than just buying a new muffler? If I just buy a magnaflow muffler and bring it to a shop to get the tubing bent and welded, am I screwing up my emissions system? I can't have this thing fail emissions next time I am due to get tested.
2. Has anybody ever considered cutting two holes in their aftermarket bumper to run the exhaust tips out? Might look a little funny, but wouldn't that protect them from being crushed? ( I haven't spent much time laying under the jeep to see if you can even route the pipes this way)
3. Round vs. oval mufflers, what's the difference?
Thanks!
Last edited by mkjeep; Sep 4, 2009 at 10:27 AM. Reason: no non sponsor links
JK Enthusiast
Joined: Aug 2009
Posts: 184
Likes: 0
From: Riverside, CA
The cat back system is just extra pipe from behind the cats to the tail pipe. They cost more because usualy they are all stainless steel pipe.
The cat back system realy won't give you any extra power even if the tubeing is larger, you will still be restricted from the cats. Changing the muffler would be about the same.
If you can find one to fit I would go with a 50 series dual outlet flowmaster. Should sound great. Nice agresive tone with out the real loud drone sound at highway speeds.
As far as emissions you won't have any problem.
You would have to cut the frame on the back of the jeep to put dual exhaust out the bumper. Sounds like a good idea if you sleave the holes correctly after cutting them.
The cat back system realy won't give you any extra power even if the tubeing is larger, you will still be restricted from the cats. Changing the muffler would be about the same.
If you can find one to fit I would go with a 50 series dual outlet flowmaster. Should sound great. Nice agresive tone with out the real loud drone sound at highway speeds.
As far as emissions you won't have any problem.
You would have to cut the frame on the back of the jeep to put dual exhaust out the bumper. Sounds like a good idea if you sleave the holes correctly after cutting them.
Thread Starter
JK Enthusiast
Joined: Sep 2007
Posts: 171
Likes: 0
From: Conifer, CO
magnaflow 11148
The cat back system is just extra pipe from behind the cats to the tail pipe. They cost more because usualy they are all stainless steel pipe.
The cat back system realy won't give you any extra power even if the tubeing is larger, you will still be restricted from the cats. Changing the muffler would be about the same.
If you can find one to fit I would go with a 50 series dual outlet flowmaster. Should sound great. Nice agresive tone with out the real loud drone sound at highway speeds.
As far as emissions you won't have any problem.
You would have to cut the frame on the back of the jeep to put dual exhaust out the bumper. Sounds like a good idea if you sleave the holes correctly after cutting them.
The cat back system realy won't give you any extra power even if the tubeing is larger, you will still be restricted from the cats. Changing the muffler would be about the same.
If you can find one to fit I would go with a 50 series dual outlet flowmaster. Should sound great. Nice agresive tone with out the real loud drone sound at highway speeds.
As far as emissions you won't have any problem.
You would have to cut the frame on the back of the jeep to put dual exhaust out the bumper. Sounds like a good idea if you sleave the holes correctly after cutting them.
Thread Starter
JK Enthusiast
Joined: Sep 2007
Posts: 171
Likes: 0
From: Conifer, CO
flowmaster 50
The cat back system is just extra pipe from behind the cats to the tail pipe. They cost more because usualy they are all stainless steel pipe.
The cat back system realy won't give you any extra power even if the tubeing is larger, you will still be restricted from the cats. Changing the muffler would be about the same.
If you can find one to fit I would go with a 50 series dual outlet flowmaster. Should sound great. Nice agresive tone with out the real loud drone sound at highway speeds.
As far as emissions you won't have any problem.
You would have to cut the frame on the back of the jeep to put dual exhaust out the bumper. Sounds like a good idea if you sleave the holes correctly after cutting them.
The cat back system realy won't give you any extra power even if the tubeing is larger, you will still be restricted from the cats. Changing the muffler would be about the same.
If you can find one to fit I would go with a 50 series dual outlet flowmaster. Should sound great. Nice agresive tone with out the real loud drone sound at highway speeds.
As far as emissions you won't have any problem.
You would have to cut the frame on the back of the jeep to put dual exhaust out the bumper. Sounds like a good idea if you sleave the holes correctly after cutting them.
I just went to the flowmaster website. Are you recommending the 50 Series three chamber 3x10, three chamber 4x8, Delta Flow, HD, or Super 50? They are all "50" Flowmasters. Thanks
JK Enthusiast
Joined: Aug 2009
Posts: 184
Likes: 0
From: Riverside, CA
Im thinking 3x10 so that it will tuck up closser to the floor pan. You need to messure to see what kind of room ther is. I think you have more room than I do. I have 2dr.
As far as delta flow, hd, or supper 50. It realy deppends on what you want like a diamond plate style or smooth body. I like the super 50 its more like their classic design.
I don't know what magnaflow offers, they usualy sound like 40 series flowmasters but they might have something similar to the 50. They are also cheaper.
As far as delta flow, hd, or supper 50. It realy deppends on what you want like a diamond plate style or smooth body. I like the super 50 its more like their classic design.
I don't know what magnaflow offers, they usualy sound like 40 series flowmasters but they might have something similar to the 50. They are also cheaper.