all muffler and exhaust questions go here!!!!!!
#78
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Year: 1993
Model: Cherokee
Engine: I6 4.0L HO
Ok well I will break it down
Flowmaster 40.
Just a lil bit louder then stock has a rumble to it and loudends around 2k and 4krpm loses most of its sound while cruseing.
Flowmaster 44.
Louder then stock. Deeper tumbler and more throaty. Stays loud even when crushing. Under hard acceleration you know she is there.
And Magana flow. Nice and deep sound. Combines the flowmaster 40 and 44.
Under hard acelleration she stays deep and clean.
Flowmaster 40.
Just a lil bit louder then stock has a rumble to it and loudends around 2k and 4krpm loses most of its sound while cruseing.
Flowmaster 44.
Louder then stock. Deeper tumbler and more throaty. Stays loud even when crushing. Under hard acceleration you know she is there.
And Magana flow. Nice and deep sound. Combines the flowmaster 40 and 44.
Under hard acelleration she stays deep and clean.
#80
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Year: 1990XJ/1989MJ
Model: Comanche
Engine: 4.0L Renix
Dan the Renix computer needs some resistance to make the oxygen sensor work properly. The system needs the exhaust to be at the sensor a tad longer so it can get a good sample.
When a less restrictive airflow exists in the exhaust the computer tries to compensate and idles rough plus changes the fuel/air ratio for the computer to see if the oxygen sensor is putting out a signal. When it sees little or no change the computer will pump more fuel into the system trying to enrich the ratio, thus causing the owner to have his system checked by a competent service person.
When a less restrictive airflow exists in the exhaust the computer tries to compensate and idles rough plus changes the fuel/air ratio for the computer to see if the oxygen sensor is putting out a signal. When it sees little or no change the computer will pump more fuel into the system trying to enrich the ratio, thus causing the owner to have his system checked by a competent service person.
#82
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Year: 1987
Model: Cherokee
Engine: 4.0 IL6
Dan the Renix computer needs some resistance to make the oxygen sensor work properly. The system needs the exhaust to be at the sensor a tad longer so it can get a good sample.
When a less restrictive airflow exists in the exhaust the computer tries to compensate and idles rough plus changes the fuel/air ratio for the computer to see if the oxygen sensor is putting out a signal. When it sees little or no change the computer will pump more fuel into the system trying to enrich the ratio, thus causing the owner to have his system checked by a competent service person.
When a less restrictive airflow exists in the exhaust the computer tries to compensate and idles rough plus changes the fuel/air ratio for the computer to see if the oxygen sensor is putting out a signal. When it sees little or no change the computer will pump more fuel into the system trying to enrich the ratio, thus causing the owner to have his system checked by a competent service person.
I recently bought 3 2.5 inch mandrel bent 90 degree exhaust tubing from summit along with 2 4ft 2.5inch pipes, Anyways I was going to make a front pipe with the 2.5 inch and weld on a magnaflow muffler with a 2.5 tail pipe. From what you saying should I return the 2.5 for some 2.25 so there is some backpressure or with the 2.5 be fine. I thought using 2.5 inch for the whole exhaust would flow nicely. What do you think?
#83
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Year: 1998
Model: Cherokee
Engine: 4.0L
Just food for thought, looks like everyone is asking about Flowmaster and Magnaflow, but I put a Gibson cat back on my 98 xj and it has been great. Has a nice sound to it at low RPM's but pretty darn quiet at freeway speeds. The noise from my mud terrains are louder. It breathes really well and have been pleased with the money I spent. Can talk on your phone and have a conversation with others in your jeep and no drone.
#85
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Year: 1992
Model: Cherokee
Engine: 4.0 I6 firepower ignition, cat-back w/ magnaflow muffler, poweraid tb spacer, optima blue top
Noticed a little while back i have an exhaust leak at the flange on the front of the cat. Upon further inspection the flange is pretty much rusted away, therefore i can't tighten down on it. Can i get an exhaust shop to weld on new flanges or am i going to have to get a new cat? Is it ok to leave it like that for a while (schedule's tight right now)?
#86
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Hey there, few questions for all you exhaust guys. Most of my exhaust brackets have rusted away into nothingness. I also suspect that my cat might be bad, and I hate the giant muffler that's on it and makes it so quiet. Anyways, I'm gonna be testing with a temp gun to see if my cat is bad. If it is I think i'm gonna replace the whole damn exhaust. So, what diameter pipe should In use? Are thrush glasspacks any good? What can I expect to spend on the cat and how on earth do o2 sensors mount on the universal ones?
P.S. I have a welder so I can fabricate brackets etc and put it all together, I just have no friggen clue what to buy. Trying to do it cheap, btw.
P.S. I have a welder so I can fabricate brackets etc and put it all together, I just have no friggen clue what to buy. Trying to do it cheap, btw.
#87
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Year: 1998
Model: Cherokee
Engine: 4.0L
I bought my xj with no cat and duals. Want to cut that off and put a straight pipe muffler and dump it before the axle. Question is, what is the diameter of the pipe that would go to the cat? Have to know what size pipe to get to connect to the muffler
#88
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Year: 1990XJ/1989MJ
Model: Comanche
Engine: 4.0L Renix
I recently bought 3 2.5 inch mandrel bent 90 degree exhaust tubing from summit along with 2 4ft 2.5inch pipes, Anyways I was going to make a front pipe with the 2.5 inch and weld on a magnaflow muffler with a 2.5 tail pipe. From what you saying should I return the 2.5 for some 2.25 so there is some backpressure or with the 2.5 be fine. I thought using 2.5 inch for the whole exhaust would flow nicely. What do you think?
#90
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Originally Posted by audioal69
Anybody running an aeroturbine muffler on an xj? My wife has one on her Mazda 3 and it sounds awesome. A little pricey but the sound was worth it.