removing one cat
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Elantra 1998-2000, Tiburon 2000
That other guys way
but they also have this listed under emmisions ctrls.
seems some do and some dont, i think mine only has 1
[ March 06, 2002, 09:53 PM: Message edited by: Viper966 ]
That other guys way
but they also have this listed under emmisions ctrls.
seems some do and some dont, i think mine only has 1
[ March 06, 2002, 09:53 PM: Message edited by: Viper966 ]
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Some do and some don't. The ones who do have the California emissions on them. This is why Our guys at SR say the cars who have 2 cats may have to relocate or remove one. I think this is wrong as well since you have to remove the vertical cat that is welded to the exhaust manifold since it does not work horizontally. For the guys who have two cats I would recomend ( I think this will turn off the CEL ) moving 2nd O2 sensor that is after the first cat to after the second cat. This should help. I am pretty sure the OBDII does not know if the second cat is there or not.
[ March 06, 2002, 10:02 PM: Message edited by: SCCA Street mod class 01 Elantra ]
[ March 06, 2002, 10:02 PM: Message edited by: SCCA Street mod class 01 Elantra ]
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QUOTE
arn:
I would like to buy a 4-1 header. Instead of relocating the cat in front, can I just remove it.
will it still pass emission? and what will happen to the car when it is remove? whats the pro and cons? Random, Red, anyones thought on this please
I would like to buy a 4-1 header. Instead of relocating the cat in front, can I just remove it.
will it still pass emission? and what will happen to the car when it is remove? whats the pro and cons? Random, Red, anyones thought on this please
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Woop's pressed the wrong button there.
I am having the same quandry as arn,I have already bought my 4-1 Header,I am just waiting for its delivery.Random has already given me some advice but I need to know if anyone knows of an exhaust company that will do a replacement exhaust which will fit from the end of the flexi pipe with an I/D of 2.1/2 inches and does not incorporate the second cat which is available on some models.Random talked about Glasspacks,What are they?
Cheers hope someone can help.
I am having the same quandry as arn,I have already bought my 4-1 Header,I am just waiting for its delivery.Random has already given me some advice but I need to know if anyone knows of an exhaust company that will do a replacement exhaust which will fit from the end of the flexi pipe with an I/D of 2.1/2 inches and does not incorporate the second cat which is available on some models.Random talked about Glasspacks,What are they?
Cheers hope someone can help.
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From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
On my cali spec car there "were" 2 cats.
The first cat was removed, I kept the second cat.
There ARE 2 cats on California emissions equipped Tiburons. On Cali spec exhausts, there are 2 cats, 1 resonator and 1 "pre muffler"
In regards to cats and headers...
You have 4 choices.
Relocate the first cat and keep the second cat. This is the "closest" to legal version. Federal law prohibits moving a functioning cat converter...but at least you are keeping both. In all states but california, and virgina, you should have no problems. This will require that your o2 sensor wiring be extended. The first 02 sensor should be before the first cat, and the second after the first cat. The first cat will more than likely foul over time, as it will not operate effectivly that far from the engine.
Dump the first cat and keep the second cat. The first cat is a "fast light" cat. That is why it is placed so close to the engine. It may not function correctly when placed farther downstream in the exhaust (see above). Again, the 02 sensors need to have their wiring extended, and the first 02 goes before the first (and only cat) and the second goes in after the cat. In states with little/no emissisions testing, this will cause no problem, but in states with strict emissions laws, you might not pass unless your car is tuned well.
Replace both cats with one "high flow" unit. Carsound is a good brand name, and there are several posts on the board of where to get carsound cats for about $50. Again, the o2 sensors will have to have their wiring extended, first one before the first cat, second one after the second cat. This should really only be used in states with NO emissions testing, as the high flow cat may not work as well as one of the stock units.
Remove both cats. This WILL trigger a CEL and is NOT RECCOMENDED. The ECU knows to look for the effects of a cat, and NO CAT will trigger a CEL. Also, one car without a cat dumps as much crap in the air as 100 cars with a cat. It's just not worth it.
When the cats are relocated, they are always put underneath the car, after the header, and after the 'flex' pipe. The o2 sensors need their position adjusted for where you put the cat. The cat should be placed as CLOSE to the engine as possible, as the cat needs HEAT to function properly. You can aid the cats function by using ceramic coated headers or heat wrapped headers and heat wraping the exhaust leading up to the cat.
The first cat was removed, I kept the second cat.
There ARE 2 cats on California emissions equipped Tiburons. On Cali spec exhausts, there are 2 cats, 1 resonator and 1 "pre muffler"
In regards to cats and headers...
You have 4 choices.
Relocate the first cat and keep the second cat. This is the "closest" to legal version. Federal law prohibits moving a functioning cat converter...but at least you are keeping both. In all states but california, and virgina, you should have no problems. This will require that your o2 sensor wiring be extended. The first 02 sensor should be before the first cat, and the second after the first cat. The first cat will more than likely foul over time, as it will not operate effectivly that far from the engine.
Dump the first cat and keep the second cat. The first cat is a "fast light" cat. That is why it is placed so close to the engine. It may not function correctly when placed farther downstream in the exhaust (see above). Again, the 02 sensors need to have their wiring extended, and the first 02 goes before the first (and only cat) and the second goes in after the cat. In states with little/no emissisions testing, this will cause no problem, but in states with strict emissions laws, you might not pass unless your car is tuned well.
Replace both cats with one "high flow" unit. Carsound is a good brand name, and there are several posts on the board of where to get carsound cats for about $50. Again, the o2 sensors will have to have their wiring extended, first one before the first cat, second one after the second cat. This should really only be used in states with NO emissions testing, as the high flow cat may not work as well as one of the stock units.
Remove both cats. This WILL trigger a CEL and is NOT RECCOMENDED. The ECU knows to look for the effects of a cat, and NO CAT will trigger a CEL. Also, one car without a cat dumps as much crap in the air as 100 cars with a cat. It's just not worth it.
When the cats are relocated, they are always put underneath the car, after the header, and after the 'flex' pipe. The o2 sensors need their position adjusted for where you put the cat. The cat should be placed as CLOSE to the engine as possible, as the cat needs HEAT to function properly. You can aid the cats function by using ceramic coated headers or heat wrapped headers and heat wraping the exhaust leading up to the cat.
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Random, As far as the first cat isn't that cat only good to work as a vertical cat? Or is that why you said it would foul because it is now mounted hirzontally or just because it is further away from the engine?
Nice to see I know more on a certain subject than someone else who thinks he knows all. Engines great, exhuast knowledge needs a little work though. smile.gif
Nice to see I know more on a certain subject than someone else who thinks he knows all. Engines great, exhuast knowledge needs a little work though. smile.gif
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Because of the "fast light" properties of the cat it will work in any position as long as there is enough heat to cause it to fuction properly. Whether it is vertical or horizontal makes no difference but the temperature does. Basicly the farther that cat (and most others) is placed away from the heat of the engine the less likely it will function properly. Actually the longer the exaust has to cool before it reaches the cat the less likely it will function properly.
[ March 07, 2002, 07:58 AM: Message edited by: DESIGN ]
[ March 07, 2002, 07:58 AM: Message edited by: DESIGN ]
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From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
As design said. The actual "orientation" of the cat (vertical vs horizonal" matters little except for exit pipe location.
The 1st cat is designed with very little heat retaining properties. This means it does not need to "absorb" much heat before reaching operating tempature. Conversely...when placed farther away from the engine, where there is less heat, it does not have the "mass" to store heat, and will cool off and cease to function when the engine is not run in high RPM mode. It is entirely possible that unless ceramic coating or heat wrap is used on the headers, it may never reach operating tempature, or still might only reach operating tempature durring high RPM full throttle runs.
This is why most people dump the first cat and replace it with a high flow unit if they only have one cat, or go with the second cat only if they have 2 cats.
The 1st cat is designed with very little heat retaining properties. This means it does not need to "absorb" much heat before reaching operating tempature. Conversely...when placed farther away from the engine, where there is less heat, it does not have the "mass" to store heat, and will cool off and cease to function when the engine is not run in high RPM mode. It is entirely possible that unless ceramic coating or heat wrap is used on the headers, it may never reach operating tempature, or still might only reach operating tempature durring high RPM full throttle runs.
This is why most people dump the first cat and replace it with a high flow unit if they only have one cat, or go with the second cat only if they have 2 cats.
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Ok understood. But what if there is only one cat and that one is vertical. The single cat (vertical unit) is different than the vertical cat on cali emissions.
Also can anyone confirm what I mentioned about the operation without a cat. Yes I know the CEL will come on but there should be no damage to the engine if there is no cat run right. It would only run a little richer.
Also can anyone confirm what I mentioned about the operation without a cat. Yes I know the CEL will come on but there should be no damage to the engine if there is no cat run right. It would only run a little richer.