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      10-09-2017, 03:42 PM   #1
misguided_will
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Catless downpipe. Can I add a cat?

Hi

I fitted a Vrsf catless and find the smell too strong and sound too loud.

Would it be possible to add a cat somewhere along the exhaust instead of replacing the vsrf with a completely new catted downpipe?

Thanks
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      10-09-2017, 04:29 PM   #2
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You could but would you really want to. It would take quite a bit of custom modification. The better bet would be to go back to stock or get a catted DP like the one from aFe.
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      10-10-2017, 12:15 AM   #3
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Short answer is yes, you can add a cheap Magnaflow/Catco catalytic converter somewhere down the line.

Two challenges to consider:

1) Post-cat o2 will need to be extended.
2) Cat efficiency maybe bad enough to trigger a CEL/code since the cat is not heated as much further down the system, therefore your post-cat o2 will read more oxygen in the exhaust.
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      10-10-2017, 01:37 AM   #4
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@TChao
Excuse my ignorance but I have a jb4 to clear codes and the O2 sensors are plugged into the Vrsf.

Are the 2 challenges still an issue?
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      10-10-2017, 01:51 AM   #5
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Btw i paid 350aud labour to fit the Vrsf. A catted Wagner would likely cost me 1200aud plus another 350 to install.

I figure adding a cat would be the most cost effective way to achieve the desired end result.
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      10-11-2017, 03:26 AM   #6
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Quote:
Originally Posted by misguided_will View Post
@TChao
Excuse my ignorance but I have a jb4 to clear codes and the O2 sensors are plugged into the Vrsf.

Are the 2 challenges still an issue?
No, if you dont care about the non-ready status of emission compliance then you can just add a cat downstream somewhere...But Why?

Smell bothering you?
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      10-11-2017, 05:04 AM   #7
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Non-ready status? In my state our cars don't need to be emissions tested unless the police or Inspectors issue u with a defect notice. Is that what you're referring to?

Yes smell and noise bothers me. The smell as I'm asthmatic and my wife is pregnant
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      10-11-2017, 07:12 AM   #8
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put the oem pipe back on and just move on? It's like 700+ to get a sport cat, who knows how much you will get from one of those.
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      10-11-2017, 07:34 AM   #9
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Quote:
Originally Posted by zinner View Post
put the oem pipe back on and just move on? It's like 700+ to get a sport cat, who knows how much you will get from one of those.
Thanks but doesn't answer my question.
And besides, a 200 cell is about $150 Aussie. Can't see an exhaust shop charging more than $250 to cut and weld on a flange for it to fit.
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      10-11-2017, 08:48 AM   #10
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seems like you should put the oem one back on.
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      10-11-2017, 09:20 AM   #11
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Quote:
Originally Posted by misguided_will View Post

Yes smell and noise bothers me. The smell as I'm asthmatic and my wife is pregnant
Sorry mate but, smell and noise comes with modded cars.
If smell and noise bother you, you should stop modding your car right a way. Now if it because the wife is pregnant then wait for the mods or get her a damn SUV. Don't cheap out for your kids.

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      10-11-2017, 09:33 AM   #12
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Quote:
Originally Posted by misguided_will View Post
Hi

I fitted a Vrsf catless and find the smell too strong and sound too loud.

Would it be possible to add a cat somewhere along the exhaust instead of replacing the vsrf with a completely new catted downpipe?

Thanks
Its doable, but I would recommend just selling the catless and getting a high quality catted set, like ER or Wagner or something similar.

In the end it will be cheaper and cleaner install and you won't have to mess with things downstream from teh cats and in the exhaust.

Mike
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      10-11-2017, 11:38 AM   #13
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Yea, would be cleaner and arguably of better quality just selling the current pipe and getting the high flow catted downpipe.
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      10-11-2017, 03:10 PM   #14
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Quote:
Originally Posted by yoandry View Post
Sorry mate but, smell and noise comes with modded cars.
If smell and noise bother you, you should stop modding your car right a way. Now if it because the wife is pregnant then wait for the mods or get her a damn SUV. Don't cheap out for your kids.

Well my wrx had a tbe, upgraded injectors, Turbo, intercooler, Cai, and a reflash and didn't smell

Thanks but the question was catless vs adding a cat to existing setup. I won't go stock.

Last edited by misguided_will; 10-11-2017 at 03:36 PM..
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      10-11-2017, 03:20 PM   #15
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If you add a Cat downstream please report back on the results.
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      10-11-2017, 03:37 PM   #16
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Quote:
Originally Posted by JaredG_F30 View Post
If you add a Cat downstream please report back on the results.
Will head to an exhaust shop in the coming weeks. Let u know what happens
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      10-12-2017, 07:02 AM   #17
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I am not sure what kind of 200 cpi cat you are talking about but I had some cheapo kooks cats on my LS6 with kooks headers and it smelled like gas still.

What did you think of the Saab turbo X listed in your sig?
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      10-12-2017, 03:00 PM   #18
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Quote:
Originally Posted by zinner View Post
I am not sure what kind of 200 cpi cat you are talking about but I had some cheapo kooks cats on my LS6 with kooks headers and it smelled like gas still.

What did you think of the Saab turbo X listed in your sig?
Stock Turbo x sounded phenomenal. Was no need for a exhaust work. Loved that car like a step child.
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      10-16-2017, 06:45 PM   #19
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Quote:
Originally Posted by misguided_will View Post
Stock Turbo x sounded phenomenal. Was no need for a exhaust work. Loved that car like a step child.
I had the 2.8T SRX, that car had some issues, but power was not one of em.
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      10-18-2017, 11:49 AM   #20
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Quote:
Originally Posted by misguided_will View Post
Hi

I fitted a Vrsf catless and find the smell too strong and sound too loud.

Would it be possible to add a cat somewhere along the exhaust instead of replacing the vsrf with a completely new catted downpipe?

Thanks
I am not sure where you are located but I have a used ER catted downpipe for sale. I had it for about two weeks but it started to throw a cel so I went catless
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      10-18-2017, 03:40 PM   #21
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@bear3525..

Thanks. Just pm'd u....
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      10-18-2017, 04:12 PM   #22
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Quote:
Originally Posted by Bear3525 View Post
I am not sure where you are located but I have a used ER catted downpipe for sale. I had it for about two weeks but it started to throw a cel so I went catless
By reading his username, it states he's in Sydney, AU. Which if you're from Long Island, NY...that'd be pricey to ship.

I run a catless DP and the cheapest fix is to simply roll the windows up and the DP's really only at it's loudest on cold starts for the first ~15 seconds.
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