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I have a Perrin uppipe installed (great mod), but worried if I replace all the exhaust system I will fail emissions. I live in North Carolina and they use the exhaust sniffers for emissions.

So can all of it be replaced and you would still be fine (no cats)?, or if not what else can I replace exhaust wise but still pass emissions.

Any thoughts, advice, and/ or experiences are greatly appreciated.

Thanks!
 

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WRX44 said:
I have a Perrin uppipe installed (great mod), but worried if I replace all the exhaust system I will fail emissions. I live in North Carolina and they use the exhaust sniffers for emissions.

So can all of it be replaced and you would still be fine (no cats)?, or if not what else can I replace exhaust wise but still pass emissions.

Any thoughts, advice, and/ or experiences are greatly appreciated.

Thanks!
You'll have to look into your local laws regarding smog equipment and visual inspections during smog checks. I live in California, and almost anything you do to increase horsepower on you car is illegal and won't pass smog. Just keep you stock parts(uppipe, stock turboback, etc.) and put it back on before you go to have your car smogged. That is what I am going to do.

Kurlee Daddee
(THE ORIGINAL)
 

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it certainly wont fail emissions testing thats for sure..may fail visual inspection, but I really doubt it unless you have a very zealous inspection official...look at how hard it is to see that sucker down there. If you really want to be sneaky you could take off the shielding on the stock up-pipe and jury rig/weld it around the aftermarket up-pipe so it looks stock. That cat only affects cold start emmissions and wont have any effect on standard emmissions tests.
 

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I am running a Stromung down pipe into the third cat.

With just a little bit of mechanical 'persuasion' we reattached the factory heat shields.

The machine still looks stock nd should pass emissions.

Regards:
The Geekqualizer:cool:
 

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twinz said:
it certainly wont fail emissions testing thats for sure..may fail visual inspection, but I really doubt it unless you have a very zealous inspection official...
Are you joking? Of course he's going to fail an emissions test with no cats. WTF?
 

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drover said:
Are you joking? Of course he's going to fail an emissions test with no cats. WTF?

My error, thought he was only referring to the up-pipe replacement.

However, it is very likely he would pass emissions with no cats whatsoever if the car is running in perfect tune and completely warmed up for the smog test but would of course fail a visual without reattaching the healshields to make it look like they were still in there. I have seen more that a few posts on i-club where people have passed with no problems doing exactly this. But I would not recommend running with no cats at all. replacing the up-pipe cat will not affect anything but cold start emissions.
 

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twinz said:
My error, thought he was only referring to the up-pipe replacement.

However, it is very likely he would pass emissions with no cats whatsoever if the car is running in perfect tune and completely warmed up for the smog test but would of course fail a visual without reattaching the healshields to make it look like they were still in there
No, it's not very likely at all that he would pass emissions with no cats, no matter how warm or perfectly tuned the engine is. I don't know who these yahoos are who say they passed their inspections with no cats. Either they're full of it or they know the right people.

WRX44: I promise you'll fail a sniffer test with no cats, so don't listen to people who tell you otherwise. You should be all right with just the up-pipe cat removed. Just make sure your engine has been running for at least 20 minutes before you get tested. If you have to wait in line, idle your engine while you're waiting. Don't shut it off. In fact that's good advice for anyone getting emissions tested, whether your exhaust is modified or not.
 

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I just had to go through this. See I got a inspection ticket for being to loud. I live in maryland were you have to get your car inspected when you buy it and then never again unless you get a ticket for it. I think you could get away with the up-pipe. But it only take like 1 and a 1/2 hours to change the hole turbo back so i just switched it and got it inspected and will switch it back this weekend.
 

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The uppipe cat only controls emissions when the car's cold. It's only a restrictor after that. Furthermore, you should be able to pass with just one high-flow cat left in the car (such as the TurboXS one). Just make sure the car is fully warmed up before the test.
 
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