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custom y pipe? single or dual cat?

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Old Aug 9, 2014 | 08:39 AM
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Default custom y pipe? single or dual cat?

Ive searched the internet but no good answer. I have a 98 Trans Am with tsp 13/4 longtubes, lid, and magnaflow catback. Im going with a custom ss y pipe. I do not plan on modding my car much in the future accept for maybe a tb and a ls6 intake.

Would i see much hp difference between have 2 cats in the y vs 1 cat after the y? The shop is charging me 180 per cat so I can save money by going with one. Would the gains be worth the extra 200 going with 2 cats?
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Old Aug 9, 2014 | 08:50 AM
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save money and go catless.
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Old Aug 9, 2014 | 01:19 PM
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Id prefer to be catted. To keep the smell down and mellow out the rasp a bit
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Old Aug 9, 2014 | 01:36 PM
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My car is set up like this. One cat after the y with a magnaflow cat back. Its ok but i am going to go cat less eventually
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Old Aug 10, 2014 | 11:12 AM
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i never noticed any smell difference... if your worried about the rasp noise, stick a bullet muffler in the I pipe
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Old Aug 10, 2014 | 12:42 PM
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Do you think a bullet muffler can visually pass as a cat converter?
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Old Aug 10, 2014 | 12:59 PM
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Originally Posted by waterbug1999
save money and go catless.
if you can go this route.


gas smell isnt bad.it doesnt bother me anyway.
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Old Aug 10, 2014 | 03:08 PM
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I don't know what kind of cats they're using but that's a huge amount of money per cat.

Think of it this way - you'd be forcing twice as much CFM through one cat. That's bound to increase back pressure. I would go with two, but I'd be looking for a better price.

I doubt a bullet would pass for a cat. You'd better be sure of what your state looks for on a visual. It typically would mean two cats, and in CA at least, they have to be OEM and in the stock position.
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Old Aug 10, 2014 | 04:56 PM
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If you go with just 1 converter I'd go with at least a 3.5" inlet/outlet (Magnaflow #59920, about $117 ea.) for better flow. I wouldn't go with a single 3" inlet/outlet converter.
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Old Aug 10, 2014 | 10:49 PM
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I live in Canada, and we always get anally abused on car parts pricing. I was lucky to find a local seller on ebay selling magnaflow metallic spun cats for 110 bucks each so I bought two. I will bring them to the exhaust guy i got my quote from, he does awesome work. Thanks for the advice guys, dual cat is the way to go, fuxk single cat restrictione
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Old Aug 11, 2014 | 10:23 AM
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Originally Posted by WS6wanted
Do you think a bullet muffler can visually pass as a cat converter?
aaa........NO lol
UNLESS
the inspector dosent care or u have a buddy that inspects cars
you could do what demonspeed did lol
http://api.viglink.com/api/click?for...20LS1TECH&txt=
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Old Aug 11, 2014 | 11:24 AM
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that too shall pass. LOL

Originally Posted by FirstGen F-Body
aaa........NO lol
UNLESS
the inspector dosent care or u have a buddy that inspects cars
you could do what demonspeed did lol
http://api.viglink.com/api/click?for...20LS1TECH&txt=
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