Cat or, no Cat?
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From: Holly Ridge, N.C.
Metal Twister:
Another idea is to pull the CAT off and just knock out all the internal material.
The stuff is about as hard as concrete, but it will come out. Then you can just put it back on the truck if you are worried about emissions inpections.
In our State, all they do is look to see if the CAT is there on diesel pickups.
They don't test the exhaust as they do in some states. But you might want to check the inspection laws in your area if you are woried about that.
Another idea is to pull the CAT off and just knock out all the internal material.
The stuff is about as hard as concrete, but it will come out. Then you can just put it back on the truck if you are worried about emissions inpections.
In our State, all they do is look to see if the CAT is there on diesel pickups.
They don't test the exhaust as they do in some states. But you might want to check the inspection laws in your area if you are woried about that.
Thread Starter
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Joined: Nov 2012
Posts: 128
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From: So Cal Diego
Metal Twister:
Another idea is to pull the CAT off and just knock out all the internal material.
The stuff is about as hard as concrete, but it will come out. Then you can just put it back on the truck if you are worried about emissions inpections.
In our State, all they do is look to see if the CAT is there on diesel pickups.
They don't test the exhaust as they do in some states. But you might want to check the inspection laws in your area if you are woried about that.
Another idea is to pull the CAT off and just knock out all the internal material.
The stuff is about as hard as concrete, but it will come out. Then you can just put it back on the truck if you are worried about emissions inpections.
In our State, all they do is look to see if the CAT is there on diesel pickups.
They don't test the exhaust as they do in some states. But you might want to check the inspection laws in your area if you are woried about that.
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Joined: Aug 2011
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From: Denmark
I pulled mine, then later I found out that there was no registration of a cat on my truck
.
3" pipe from where the cat used to be and out the back, after about a year I put a free flow muffler on it, it was a little loud.
Around here they smog test, no load and let it rev, not to worry about on a stocker, or just tighten the starwheel a bit...
It did make a difference when it "fell off", much better flow, but as others have done, I still have it somewhere just in case.
Slev
.3" pipe from where the cat used to be and out the back, after about a year I put a free flow muffler on it, it was a little loud.
Around here they smog test, no load and let it rev, not to worry about on a stocker, or just tighten the starwheel a bit...
It did make a difference when it "fell off", much better flow, but as others have done, I still have it somewhere just in case.
Slev
Thread Starter
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Joined: Nov 2012
Posts: 128
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From: So Cal Diego
I pulled mine, then later I found out that there was no registration of a cat on my truck.
3" pipe from where the cat used to be and out the back, after about a year I put a free flow muffler on it, it was a little loud.
Around here they smog test, no load and let it rev, not to worry about on a stocker, or just tighten the starwheel a bit...
It did make a difference when it "fell off", much better flow, but as others have done, I still have it somewhere just in case.
Slev
.3" pipe from where the cat used to be and out the back, after about a year I put a free flow muffler on it, it was a little loud.
Around here they smog test, no load and let it rev, not to worry about on a stocker, or just tighten the starwheel a bit...
It did make a difference when it "fell off", much better flow, but as others have done, I still have it somewhere just in case.
Slev
Now I'm in So Cal and no smog check is required till 97 I believe. So for the most part I think Id be OK but I think Id rather gut the system and let it breath rather than have an inefficient plugged up cat. Probably not a good Idea to say I'm going to gut it on a forum... 
So I'm going to leave it as is and just see what happens.
Thanks for the input guys!
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From: Holly Ridge, N.C.
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Clean or replace it for sure if its clogged but otherwise why mess with it then get in possible legal trouble for removing it or fail future inspections either visual or smog test? Someone put a full no cat 4" exhaust on mine before I got it and it passes inspection but for how long no one knows. I would rather the cat be on there because the exhaust smells horrible and if you stand back there to long I think you would pass out.
Thread Starter
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From: So Cal Diego
I tell you what, I don't think the exhaust could be any ranker than it is now. With that said I think I will check it for being plugged up. If it is I will most likely repace it with a new one. Thanks for all the good reply's guys. Really helped a lot and it is appreciated.
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Joined: Mar 2002
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From: Holly Ridge, N.C.
Clean or replace it for sure if its clogged but otherwise why mess with it then get in possible legal trouble for removing it or fail future inspections either visual or smog test? Someone put a full no cat 4" exhaust on mine before I got it and it passes inspection but for how long no one knows. I would rather the cat be on there because the exhaust smells horrible and if you stand back there to long I think you would pass out.
cromulius:
In my State of N.C., we have mandatory state inpections on all vehicles.
In our county, all they do on diesel vehicles, is a "visual inspection" to see if the catalytic converter is on the vehicle according to their computers and manafacturers data on whether that vehicle came equipped with a CAT or not. If you have the CAT there they go no further. If they don't see the CAT, they will tell you to put on on and then come back. Now, there are a few "emissions counties" in N.C. that do actual diesel emission exhaust tests with "opacity meters"and related exhaust analyzers. Those machines CAN detect if the CAT has been "gutted." The CAT on my 2006 is on the truck but is "empty" inside and does NOT sound bad nor does "smell horrible."
In my opinion, it smells about the same as a truck that still has a CAT.
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Joined: Mar 2002
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From: Holly Ridge, N.C.
Let me also add something about the diesel exhaust smell.
My 1996 Dodge CTD "race truck" which BTW, is a daily driver has that "terrible smeling exhaust" some of you mentioned here.
The reason for that is I use a on-road diesel fuel but add pure cetane to the fuel along with lubricity and sulphur additives to protect my pump and injectors.
My 1996 Dodge CTD "race truck" which BTW, is a daily driver has that "terrible smeling exhaust" some of you mentioned here.
The reason for that is I use a on-road diesel fuel but add pure cetane to the fuel along with lubricity and sulphur additives to protect my pump and injectors.
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Joined: Mar 2002
Posts: 8,311
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From: Holly Ridge, N.C.
Yes Sir,.....when I ran two-stroke oil I could smell it in the exhaust too.
I went to "Stanadyne" a few years ago in my 2006 and don't smell anything from the exhaust with that additive though.
