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CVO Technical => Intake/Exhaust/ECM => Topic started by: Threephase on April 30, 2021, 11:47:34 PM

Title: 131” header pipe
Post by: Threephase on April 30, 2021, 11:47:34 PM

Does anyone know what is different about the catted header that comes with the 131” upgrade kit? I compared it to a stock head pipe and cannot tell a difference in appearance. Even the catalyst material inside looks the same. Same size O2 bungholes. Other than a different part number they appear identical.

Title: Re: 131” header pipe
Post by: cvosjoe on May 01, 2021, 06:45:54 AM

Quote from: Threephase on April 30, 2021, 11:47:34 PM

Does anyone know what is different about the catted header that comes with the 131” upgrade kit? I compared it to a stock head pipe and cannot tell a difference in appearance. Even the catalyst material inside looks the same. Same size O2 bungholes. Other than a different part number they appear identical.

The head pipe in the Stage IV 131 kit is rated Euro4. There is more catalyst material inside the head pipe. It is more restrictive than the regular catalyst head pipe for US models.

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Title: Re: 131” header pipe
Post by: Threephase on May 01, 2021, 10:06:23 AM

So they are choking down the 131”  with a more restrictive catalyst. Their description of the header makes it seem just the opposite.

Title: Re: 131” header pipe
Post by: cvosjoe on May 01, 2021, 07:51:09 PM

Quote from: Threephase on May 01, 2021, 10:06:23 AM

So they are choking down the 131”  with a more restrictive catalyst. Their description of the header makes it seem just the opposite.

There's no way the US head pipe would pass EPA standards because of the larger cubic inch engine. That's why the Euro4 rating. I used the head pipe from the kit in my build so I could retain the warranty.

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