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Question about Cats and Exhaust

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Old Feb 3, 2015 | 12:57 PM
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Default Question about Cats and Exhaust

to my question on Cats.
Does it matter how far away from the motor they are? Do they function differently right off the manifold or a few feet back in the system?

Im SO TIRED of being gassed out, tuning helped but I just need cats.

the only place they can go on my system is here-


I think I can make them fit there but is it too far away and would I just end up clogging them or something?
I know they need to get hot to function properly but dont know if they will got hot enough that far back especially since I have headers that run cooler anyway.

let me know cause i dont know much about cats.
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Old Feb 3, 2015 | 01:01 PM
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Moving to external.

I would say you need to make sure you can get them hot enough to function properly. LG sells a catted version. Maybe see if you can get the specs for the x-pipe from them and have your cats installed in the same location on your ORX.
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Old Feb 3, 2015 | 01:08 PM
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Originally Posted by JakeFusion
Moving to external.

I would say you need to make sure you can get them hot enough to function properly. LG sells a catted version. Maybe see if you can get the specs for the x-pipe from them and have your cats installed in the same location on your ORX.
Unfortunately I found out my Exhaust is actually Borla instead of LG's they are very similar but borla doesnt offer a Catted system.. On mine you can see that the xpipe is right off the collectors. on the lg system, their are connection pipes and then the X.

So literally my only option is what I posted or I guess I could cut off the collector and weld them there but id rather not do that. Do they get ruined if they arent hot enough? or do they just not filter as well?
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Old Feb 3, 2015 | 01:50 PM
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I ran into this same issue when doing headers and true duals. The shop said they would eventually clog if too far back. The cut off part of the header, welded one in there to get it close.
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Old Feb 3, 2015 | 01:57 PM
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So literally my only option is what I posted or I guess I could cut off the collector and weld them there but id rather not do that. Do they get ruined if they arent hot enough? or do they just not filter as well?
Do not cut the collector, that seems excessive for what you need. Most LT systems place the cats right after the collector so that's where you should put yours also. Keeps the value of your pipes and you want a proper collector to even out the gases otherwise the headers don't perform properly.
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Old Feb 3, 2015 | 02:01 PM
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Im not even sure if thats an option on my system because they would literally have to cut off the whole collector using the smallest cat ive been able to find. I wonder if it would work if I found a stainless cat and then ceramic coated it or wrapped it to keep the heat in. bad idea?
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Old Feb 3, 2015 | 02:03 PM
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If I place it right after the X than thats only about a foot further away. is that enough length to make any difference?
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Old Feb 3, 2015 | 02:42 PM
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not sure what state you are in, so I don't know what kind of inspection you have to go through, but the federal law (EPA) says that cats must be within 3 inches of where the factory put them and you have to have the same number of cats as the factory installed.
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Old Feb 3, 2015 | 02:47 PM
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Originally Posted by OwieVT
not sure what state you are in, so I don't know what kind of inspection you have to go through, but the federal law (EPA) says that cats must be within 3 inches of where the factory put them and you have to have the same number of cats as the factory installed.
Im in utah but the xpipe would be where they were from the factory. so I guess mine would be about 10 inches from where they were. I have friends that pass me so I highly doubt ill have that problem. My main concern is just not wanting to install them and go through all the hassle if they are just going to clog up from not getting hot enough farther back in the system
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Old Feb 3, 2015 | 03:34 PM
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Just got off the phone with an exhaust shop. They said its ok if the Cat is further back in they system, it will just take longer for it to "light". but it wont cause it to clog.

So basically on cold start ups it will still think ect but once Its been running/driving for a bit it should heat up enough to start working
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