Cat removed, anything I should adjust?
Thread Starter
Seasoned Member
Joined: Dec 2018
Posts: 267
Likes: 6
From: NJ
Year: 1994/ 96 engine
Model: Cherokee (XJ)
Engine: 4.0 HO Straight 6 Baby!
So I was planning on removing the catalytic converter anyway and since the muffler was banging the crossmember I had my mechanic do it...Ran a Straight pipe to my Glasspack Muffler/aka cherry bomb...sounds like A muscle car now! Just wanted to know is their anything else I should be changing or am I fine? Would a new intake make a difference? Not really on my mind...but just wondering. I certainly noticed an increase in power without the cat. My jeep is slowly becoming one mean beast. No check engine light or anything. Will this screw up the sensors? Any vehicle below 95 in jersey needs no inspection. Hence why I picked a 94 cherokee. I can literally do whatever I want...within reason. So any thoughts lemme know but I am lovin it right now! Thanks in advance
CF Veteran


Joined: Mar 2015
Posts: 1,203
Likes: 154
From: Northern CT
Year: 1995
Model: Cherokee
Engine: Turbo 4.0
I've run my 95 for years the same way you are with no issues. In CT 95 and down needs to pass an exhaust gas analysis on a dyno as well as visual cat inspection. Even at 280k and sans cat I still pass every time.
Senior Member
Joined: Sep 2018
Posts: 802
Likes: 140
From: NJ
Year: 1992
Model: Cherokee (XJ)
Engine: 4.0
It may not need inspection in NJ, but I think the cat would have to be there since it originally was equipped on the vehicle when it came from the factory. Granted, there isn't much of a chance you would be found out, but there is still a chance. No cat and a glasspack is pretty likely to get you stopped by State Police or local cops. And knowing the state of NJ, there will be a whopper of a fine.
I think Magnaflow makes a converter that isn't too bad for performance. You could probably use it and not have too much performance loss.
I think Magnaflow makes a converter that isn't too bad for performance. You could probably use it and not have too much performance loss.
Thread Starter
Seasoned Member
Joined: Dec 2018
Posts: 267
Likes: 6
From: NJ
Year: 1994/ 96 engine
Model: Cherokee (XJ)
Engine: 4.0 HO Straight 6 Baby!
It may not need inspection in NJ, but I think the cat would have to be there since it originally was equipped on the vehicle when it came from the factory. Granted, there isn't much of a chance you would be found out, but there is still a chance. No cat and a glasspack is pretty likely to get you stopped by State Police or local cops. And knowing the state of NJ, there will be a whopper of a fine.
I think Magnaflow makes a converter that isn't too bad for performance. You could probably use it and not have too much performance loss.
I think Magnaflow makes a converter that isn't too bad for performance. You could probably use it and not have too much performance loss.
Senior Member



Joined: Sep 2015
Posts: 939
Likes: 71
From: Abysmo, NJ
Year: 1999
Model: Cherokee
Engine: 4.0
Minor nit, it is pre-1996 vehicles that are not inspected in NJ. (Basically, only OBD-II vehicles are tested. Due to rust there are few older vehicles around.) One of my vehicles is a 1995 model and inspection is not required. Shortly after the law changed I had an a**hole cop in Lumberton, NJ pull me over for an "expired inspection sticker." Jerk kept me on the side of the road for a good 15-20 minutes.
I guess when he called the stop in they set him straight since I didn't get a ticket. (Wish I had, would have had some real fun with that.) I went over to the HQ to lodge a complaint and just got a runaround. Anyone driving through that town should be aware that Lumberton cops suck. Anyhow, enough ranting - sounds like you have a hell of a setup. Nice that you know some decent guys on the force, I just hope a cop you don't know that has a chip on his shoulder doesn't give you a hard time over it.
I guess when he called the stop in they set him straight since I didn't get a ticket. (Wish I had, would have had some real fun with that.) I went over to the HQ to lodge a complaint and just got a runaround. Anyone driving through that town should be aware that Lumberton cops suck. Anyhow, enough ranting - sounds like you have a hell of a setup. Nice that you know some decent guys on the force, I just hope a cop you don't know that has a chip on his shoulder doesn't give you a hard time over it.
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
I did leave Pasadena, downwind of LA when I was 4. I still remember not being able to inhale without a clamping feeling in my chest. Believe it or not we all reap huge benefit from these smog "strategies". We who breathe air anyway. The life-layer on Earth is relatively as thick as the wax on a bolleing ball, we would be wise to not foul it up.
Last edited by DFlintstone; Feb 14, 2019 at 09:30 PM.
Senior Member



Joined: Sep 2015
Posts: 939
Likes: 71
From: Abysmo, NJ
Year: 1999
Model: Cherokee
Engine: 4.0
I understand where you're coming from but there's a reason decades-old vehicles are not inspected here. There are so few left that you could probably take the cats off all of them and it would not make a noticeable difference. The Los Angeles area has unusually high tendency to develop smog problems due to its geography and a much larger population of old cars due to the mild climate.
Trending Topics
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
I'm talking about 1964. They weren't old, just belching uncontrolled quantities of hydrocarbons! The result looked like fog, hence the term"smog". In some cities I hear the exhaust from a modern vehicle is cleaner than the air it's taking in! All a functioning catalytic converter does is burn gas that the engine didn't. Unlike lower combustion ratios to lower Nox, retarded timing, or exhaust gas re-circulation, the CC is relatively harmless for performance/economy.
CF Veteran




Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
I'm talking about 1964. They weren't old, just belching uncontrolled quantities of hydrocarbons! The result looked like fog, hence the term"smog". In some cities I hear the exhaust from a modern vehicle is cleaner than the air it's taking in! All a functioning catalytic converter does is burn gas that the engine didn't. Unlike lower combustion ratios to lower Nox, retarded timing, or exhaust gas re-circulation, the CC is relatively harmless for performance/economy.
Not to mention, am not sure how you get around the second O2 sensor throwing that code. Codes are a deal breaker on any inspection.
Last edited by 97grand4.0; Feb 15, 2019 at 05:31 AM.
Senior Member



Joined: Sep 2015
Posts: 939
Likes: 71
From: Abysmo, NJ
Year: 1999
Model: Cherokee
Engine: 4.0
heh. Hear ya. Because of the catalytic converters, this guy never even saw that kind of smog so to him it's like...what's the problem? Lol
Not to mention, am not sure how you get around the second O2 sensor throwing that code. Codes are a deal breaker on any inspection.
Not to mention, am not sure how you get around the second O2 sensor throwing that code. Codes are a deal breaker on any inspection.
Worst problem we had was in the northern part of the state around the Newark area due to oil refineries. People up there used to say "smells like money." (Those of us from central and southern NJ had a different description for it.) Is the air cleaner today? Of course. However the LA-style smog problem being described was virtually unknown here even in the pre-cat days.
Today there is no inspection on the few pre-1996 vehicles left here so the error code is not an issue.
CF Veteran




Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
yeah here in NY a check engine light is a fail.
Ah yes, the days I recall well. Pollution aside, there was nothing like a 10 year old v8 thunder with dual wide open exhaust, maybe a thrush straight glass pack muffler or two. and clutch and floor shifter. That didn't cost $45,000. something just ...American...about it.
Ah yes, the days I recall well. Pollution aside, there was nothing like a 10 year old v8 thunder with dual wide open exhaust, maybe a thrush straight glass pack muffler or two. and clutch and floor shifter. That didn't cost $45,000. something just ...American...about it.
CF Veteran


Joined: Mar 2015
Posts: 1,203
Likes: 154
From: Northern CT
Year: 1995
Model: Cherokee
Engine: Turbo 4.0
Again, I've had zero issues running the setup you describe without DTCs. If your engine has been maintained you can pass a sniff test without a cat as I have done. Same emissions parameters so no smog created.
CF Veteran


Joined: Jan 2017
Posts: 3,407
Likes: 398
From: Connecticut
Year: 2000
Model: Cherokee (XJ)
Engine: 4.0
I mean, if they were so inclined?
Inquiring minds want to know...
Senior Member
Joined: Sep 2018
Posts: 802
Likes: 140
From: NJ
Year: 1992
Model: Cherokee (XJ)
Engine: 4.0
Minor nit, it is pre-1996 vehicles that are not inspected in NJ. (Basically, only OBD-II vehicles are tested. Due to rust there are few older vehicles around.) One of my vehicles is a 1995 model and inspection is not required. Shortly after the law changed I had an a**hole cop in Lumberton, NJ pull me over for an "expired inspection sticker." Jerk kept me on the side of the road for a good 15-20 minutes.
I guess when he called the stop in they set him straight since I didn't get a ticket. (Wish I had, would have had some real fun with that.) I went over to the HQ to lodge a complaint and just got a runaround. Anyone driving through that town should be aware that Lumberton cops suck. Anyhow, enough ranting - sounds like you have a hell of a setup. Nice that you know some decent guys on the force, I just hope a cop you don't know that has a chip on his shoulder doesn't give you a hard time over it.
I guess when he called the stop in they set him straight since I didn't get a ticket. (Wish I had, would have had some real fun with that.) I went over to the HQ to lodge a complaint and just got a runaround. Anyone driving through that town should be aware that Lumberton cops suck. Anyhow, enough ranting - sounds like you have a hell of a setup. Nice that you know some decent guys on the force, I just hope a cop you don't know that has a chip on his shoulder doesn't give you a hard time over it.Most likely you will never get caught with the catalytic converter thing, but there are plenty of situations where tickets can be given for bs reasons. Don't get me wrong, I support law enforcement, but there can sometimes be complete overreach by police officers. The mother of a friend of mine was pulled over and ticketed for expiring registration. It wasn't expired, but it expired at the end of the month (a few weeks away). They made her park the car in a nearby parking lot and had my friend come get her. Granted, the ticket was dismissed but she still had to pay the court fees.
Just my .02, if you are not worried about it, then go nuts.


