true duals with cats?
Thread Starter
Staging Lane
Joined: Apr 2010
Posts: 88
Likes: 0
From: School in Arizona, summers in Illinois
true duals with cats? I was just wondering if it's possible to run LT's to true dual exhaust with catalytic converters...I know there's an option of catted y-pipe or ORY but TD's definitely have my interest right now 
They can be located in the same place as they are on a catted y-pipe. Duals don't really start looking different until after that point, right before the Y or X or H junction. Have you looked at the True Duals sticky?
https://ls1tech.com/forums/showthrea...ferrerid=13535
https://ls1tech.com/forums/showthrea...ferrerid=13535
True duals are about as illegal exhaust as you can get, so putting cats on it still might not get you by emissions unless someone can pass you. In which case, why bother wasting the money?
lol...where does the OP mention that he's trying to pass emissions? There are other reasons for running cats than making the feds happy. And please explain why true duals are the most illegal exhaust you can get, I need a good laugh this evening.
Well, most are dumped at the axle, which is illegal since the exhaust exits underneath what's still considered the passenger cabin, and most people running true duals are also running long tubes, and as far as I'm aware, anything that moves the cats qualifies as "Yep, that's not gonna work" for a visual inspection. Not to mention all the broken noise ordinances.
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Verdad Gallardo I am saying duals are illegal, not cats.
Duals move the cat(s) if you keep them, duals eliminate the cat if you go that route, moves the placement of muffler, and theres probably more. These are all ILLEGAL in my state and will cause you to fail a legitimate emissions test. How are those facts for a laugh?
Also, I said "about" and did not say they are the most illegal. longtubes with a muffler off the collector would probably take that, or just open headers.
Also, I said "about" and did not say they are the most illegal. longtubes with a muffler off the collector would probably take that, or just open headers.
That is funny because duals don't move the cats, LT's do. I just don't understand why you guys got off on this illegal rant. The OP never asked for a lawyers opinion that I can tell, just had a question about running duals and cats.
I am saying duals are illegal, not cats.
Duals move the cat(s) if you keep them, duals eliminate the cat if you go that route, moves the placement of muffler, and theres probably more. These are all ILLEGAL in my state and will cause you to fail a legitimate emissions test. How are those facts for a laugh?
Also, I said "about" and did not say they are the most illegal. longtubes with a muffler off the collector would probably take that, or just open headers.
Duals move the cat(s) if you keep them, duals eliminate the cat if you go that route, moves the placement of muffler, and theres probably more. These are all ILLEGAL in my state and will cause you to fail a legitimate emissions test. How are those facts for a laugh?
Also, I said "about" and did not say they are the most illegal. longtubes with a muffler off the collector would probably take that, or just open headers.
I've got dumped duals with no cats...WV's a no-emissions state and all I have to do it slap on pipe extensions to get the exhaust out the back (I can ride around with 5 people in the back of a pickup truck legally, but if I move the exhaust exit location from the stock position, my car fails inspection...typical legal bullshit).
Some people don't realise that changing exhaust setups can fubar their luck when it's time for a visual/emissions inspection. Aside from that, I think it was simply thinking that the OP wanted to keep the cats to be legal rather than changing the exhaust sound or cutting down on fumes.
I've got dumped duals with no cats...WV's a no-emissions state and all I have to do it slap on pipe extensions to get the exhaust out the back (I can ride around with 5 people in the back of a pickup truck legally, but if I move the exhaust exit location from the stock position, my car fails inspection...typical legal bullshit).
I've got dumped duals with no cats...WV's a no-emissions state and all I have to do it slap on pipe extensions to get the exhaust out the back (I can ride around with 5 people in the back of a pickup truck legally, but if I move the exhaust exit location from the stock position, my car fails inspection...typical legal bullshit).
Thread Starter
Staging Lane
Joined: Apr 2010
Posts: 88
Likes: 0
From: School in Arizona, summers in Illinois
oh ok sorry guys, i must have skipped over the part mentioning cats in the td's sticky. anyways, yeah i was wondering about that to pass emissions. i live in illinois and all they do for emissions is plug in under the steering wheel. i didn't know that they're illegal...even if you keep the cats and all emissions stuff, LT's are illegal?
lol...about time you get back in here and give us some more information. 
Everything the lawyers said above is true...but is based upon the state they live in. I live in La. and they plug in and read the computer codes but don't do a visual inspection under the car for placement of cats, mufflers and pipes and they don't sniff the tailpipe....sounds like the same issue in your state. You can get away with LT's in that case with or without cats as long as the car isn't throwing codes. How you go about doing that is up to you. I'm sure eventually all states will have strict laws similar to Ca., but for now, every state is different on what they look for during an inspection. And just because you put cats on LT's doesn't necessarily mean you will pass a sniffer test either.
Everything the lawyers said above is true...but is based upon the state they live in. I live in La. and they plug in and read the computer codes but don't do a visual inspection under the car for placement of cats, mufflers and pipes and they don't sniff the tailpipe....sounds like the same issue in your state. You can get away with LT's in that case with or without cats as long as the car isn't throwing codes. How you go about doing that is up to you. I'm sure eventually all states will have strict laws similar to Ca., but for now, every state is different on what they look for during an inspection. And just because you put cats on LT's doesn't necessarily mean you will pass a sniffer test either. Thread Starter
Staging Lane
Joined: Apr 2010
Posts: 88
Likes: 0
From: School in Arizona, summers in Illinois
haha i know but we just started team conditioning this week so i haven't been able to go on here as much as usual...anyways i would get it tuned anyways cause i hate having the check engine light on. so sounds like this might be in my future haha thanks guys
On The Tree
Joined: Sep 2010
Posts: 168
Likes: 0
From: Plano,TX
I've got a pretty loud car on my hands. I recently had my car inspected and it passed beautifully. Exhaust setup is in the sig. Here's a clip of her idling. I passed with the exhaust seen/heard there. http://www.youtube.com/watch?v=LLl-Nt-3KaM
