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Focal Distortion
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Depends on the type of inspection they do. if all the do is hook up the computer and read it, you should be fine. If they do a visual inspection and start poking around than probably not. You could have a HFC installed in the first section of piping after the flex but then you loose most of the effects of having a header in the first place. What other mods have you done to increase power so far?
 

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Depends on the type of inspection they do. if all the do is hook up the computer and read it, you should be fine. If they do a visual inspection and start poking around than probably not. You could have a HFC installed in the first section of piping after the flex but then you loose most of the effects of having a header in the first place. What other mods have you done to increase power so far?
performance wise, removed resonator and put a high flow muffler on. my next one is going to be a steeda intake. what is an HFC? flex? (sorry, pretty new to this)
 

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HFC= high flow cat. Flex is the flex pipe
 

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I have been told you cannot move the position of the cat. Yes technically its after the "header pipes", but not in the same exact position.
There is one cat in the exhaust manifold- or just after, but it's in the same piece of pipe and not removable. The flex pipe is also part of that first piece of exhaust, and I refer to the whole thing as the mani-cat. Then there's another cat after the flange that disconnects the mani-cat.

The only problem with removing it and installing a single cat + header, besides emissions regs, is the O2 sensor programming. In an 05 there are 2 sensors- one before the mani-cat, and one before the 2nd cat.

After the header + cat are installed, your main enemy will end up being noise. I've proposed a few times that I think the exhaust piping should be nothing but glass packs, elbows, and whatever reflective or packed muffler you can fit in your application. I'm not sure if I'll ever have a header on my car, so I don't know if I'll ever put that theory to test.
 

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There is one cat in the exhaust manifold- or just after, but it's in the same piece of pipe and not removable. The flex pipe is also part of that first piece of exhaust, and I refer to the whole thing as the mani-cat. Then there's another cat after the flange that disconnects the mani-cat.

The only problem with removing it and installing a single cat + header, besides emissions regs, is the O2 sensor programming. In an 05 there are 2 sensors- one before the mani-cat, and one before the 2nd cat.

After the header + cat are installed, your main enemy will end up being noise. I've proposed a few times that I think the exhaust piping should be nothing but glass packs, elbows, and whatever reflective or packed muffler you can fit in your application. I'm not sure if I'll ever have a header on my car, so I don't know if I'll ever put that theory to test.
I'm well aware the manifold and cat is one piece. I was a certified emission inspector years ago, a replacement cat had to be installed in the exact location of the factory cat. Some inspectors may let it go if it has a cat of any kind in any location, others may not.
 
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