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Old Nov 13, 2019 | 03:42 PM
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I'm just starting to install a L83 into a Defender 110 and trying to plan out the exhaust. I got some mini Cats hoping I could fit them near the front but it's ugly tight up there. I know they should run hot but it looks like the easiest place to put them would be around the rear of the transmission (6L80). I got a stand alone harness from Speartech with just the front O2 sensors so I don't have to worry about that, does that sound like it would be okay?

Thanks,
Sean
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Old Nov 13, 2019 | 05:11 PM
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If that is where the original cat(s) were, if it had any, you'll be fine legally.
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Old Nov 13, 2019 | 05:54 PM
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In the trash can!
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Old Nov 13, 2019 | 08:44 PM
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Originally Posted by 01CamaroSSTx
In the trash can!

I hear ya lol.

It was a diesel Defender that I didn't pay attention to where the originals were, I don't even think I need them but not sure and I will have to do an inspection once I'm done as it came from the country Georgia down by Turkey. I was just wondering if they would get hot enough to work being that far back or if they would just get clogged and cause problems.

Sean
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Old Nov 13, 2019 | 09:12 PM
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If they end up alongside or near the tail shaft housing you should be fine. Exhaust is still plenty hot by that point.
Which state are you in, just out of curiosity?
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Old Nov 13, 2019 | 10:03 PM
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Hopefully the state of Alberta one day lol. Canada.

Thanks, that will make life so much easier.

Sean
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Old Nov 13, 2019 | 11:23 PM
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Does Alberta do smog inspection?
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Old Nov 14, 2019 | 08:01 AM
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Nope, not yet anyway.
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Old Nov 14, 2019 | 10:36 AM
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Then why worry about it?
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Old Nov 14, 2019 | 03:22 PM
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The way things are going I wouldn't be surprised if they didn't start doing smog tests. I've torn this Defender down to the frame and don't want any problems insuring or registering it. I don't mind the cats anyways, going from 115hp diesel to almost 400hp gen V automatic so it'll be a great improvement anyway. I just always thought they had to be as close to the manifolds as possible.

Sean
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Old Nov 14, 2019 | 05:55 PM
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Originally Posted by sgo70
The way things are going I wouldn't be surprised if they didn't start doing smog tests. I've torn this Defender down to the frame and don't want any problems insuring or registering it. I don't mind the cats anyways, going from 115hp diesel to almost 400hp gen V automatic so it'll be a great improvement anyway. I just always thought they had to be as close to the manifolds as possible.

Sean
You are correct in your thoughts. Cats always work more efficiently being as close as possible to the manifold/header.
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Old Nov 14, 2019 | 06:50 PM
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I've seen a lot of cases where the cats are alongside the tranny or thereabouts. Much further back and they likely don't function as well. As said, the closer to the engine the better, with them attached right below the manifolds the better.
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