Catalytic coverter question
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Launching!
Joined: Feb 2010
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From: Houston
Catalytic coverter question Right now I am running a pacesetter long tubes, ORYP w/ original cat welded in and a Borla catback.
The inspection guy wants a cat on each arm of the y-pipe rather than just the one in the original spot, or one cat after the two tubes join so ALL exhaust is filtered. Should I add a second one or move the existing down further towards the catback?
If I went with two, what should I buy? I was browsing Summit and there are million different cat types. I was concerned about pipe diameter with the ypipe and header matching the cat, as well as overall size of the unit, since its cramped in there.
Anyone have any input?
The inspection guy wants a cat on each arm of the y-pipe rather than just the one in the original spot, or one cat after the two tubes join so ALL exhaust is filtered. Should I add a second one or move the existing down further towards the catback?
If I went with two, what should I buy? I was browsing Summit and there are million different cat types. I was concerned about pipe diameter with the ypipe and header matching the cat, as well as overall size of the unit, since its cramped in there.
Anyone have any input?
tell the inspection guy to go **** himself, not sure of the year of your car but some of them only came with 1 cat.
That makes me mad just reading it. Noone should ever tell you to put more cats on than were required when it was stock, infact that guy needs to quit being captian green. Your only concearn is that your car passes. Its a pass/fail test.... If you passed, tell that guy to go find a bag of ******. Even if your car had 2 and its only got 1 now, if it still passed the sniffer then it still passed.
That makes me mad just reading it. Noone should ever tell you to put more cats on than were required when it was stock, infact that guy needs to quit being captian green. Your only concearn is that your car passes. Its a pass/fail test.... If you passed, tell that guy to go find a bag of ******. Even if your car had 2 and its only got 1 now, if it still passed the sniffer then it still passed.
tell the inspection guy to go **** himself, not sure of the year of your car but some of them only came with 1 cat.
That makes me mad just reading it. Noone should ever tell you to put more cats on than were required when it was stock, infact that guy needs to quit being captian green. Your only concearn is that your car passes. Its a pass/fail test.... If you passed, tell that guy to go find a bag of ******. Even if your car had 2 and its only got 1 now, if it still passed the sniffer then it still passed.
That makes me mad just reading it. Noone should ever tell you to put more cats on than were required when it was stock, infact that guy needs to quit being captian green. Your only concearn is that your car passes. Its a pass/fail test.... If you passed, tell that guy to go find a bag of ******. Even if your car had 2 and its only got 1 now, if it still passed the sniffer then it still passed.
You obviously don't have a clue of what is going on....
I would put another one on the other side since its easier to flow more volume through two cats than one of similar size.
dont know how my post is stupid.
If his car has 1 cat on it to begin with why does he need 2?
Maybe im missunderstanding what you mean by inspector. I was assuming you were doing emissions testing?
If his car has 1 cat on it to begin with why does he need 2?
Maybe im missunderstanding what you mean by inspector. I was assuming you were doing emissions testing?
My $0.02 That is the point of contention: if the car originally came with only one cat, then it probably has either a single post-cat O2 sensor, or two O2 sensors, one pre-cat and one post. To "require" a second cat (from an emissions piont of view) makes little to zero sense given the fact that your vehicle, by virtue of the addition of headers, does not flow any more exhaust gases (in terms of total volume), it simple does a more efficient job of removing that same volume of exhaust. Additionally, without 4 O2 sensors, a dual cat system will not assist the PCM in selecting the proper injector pulse width, so the engine runs "cleaner".
"trilkb" might be a bit brash, but I do believe he's got a point; if the car originally came with one cat, then an inspector cannot simply make a requirement for a second to be added. If the car does indeed "pass" the sniffer test, then baring any specific state laws that allow such activity, then I cannot see this as legal. I'd (respectfully) ask the inspector why 2 cats and then ask him to back his/her position up via a specific state law.
(If possible, I'd consult with a second inspector as well.)
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From what i understand ALL EXHAUST GASES MUST PASS THROUGH A CAT. With the setup that LarsV8 has is one cat is welded to one side of the ORY and the other is free flowing, not passing through a cat. The inspector sees this and states that all exhaust must pass through a cat in some form, Thus giving the option of adding a cat to the other side, completing the requirement. The other option is removing the existing cat and adding one after the y in the ORYP. Both options fulfill the requirements.
so yes trilkb your post was retarded.
so yes trilkb your post was retarded.
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Launching!
Joined: Feb 2010
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From: Houston
Hi Great, thanks for the info.
I brought up the single cat from factory point and was shot down since I added the headers. While I didn't ask for the specific law, I can see the tech's point about both header banks needing to be "filtered"
This car is a LE2 heads / cam car with a 226/232 cam which probably won't pass the sniffer in itself, especially with one pipe wide open. I believe the extra cat might give me a chance to pass or atleast get it close enough for the mechanic to let it slide.
Furthermore, I feel the car is a bit raw, as in smells very gassy and I think adding the second cat will cut down on this.
I brought up the single cat from factory point and was shot down since I added the headers. While I didn't ask for the specific law, I can see the tech's point about both header banks needing to be "filtered"
This car is a LE2 heads / cam car with a 226/232 cam which probably won't pass the sniffer in itself, especially with one pipe wide open. I believe the extra cat might give me a chance to pass or atleast get it close enough for the mechanic to let it slide.
Furthermore, I feel the car is a bit raw, as in smells very gassy and I think adding the second cat will cut down on this.
I was imagining 1 cat on the I pipe after the y pipe, i think Great421 was as well. Putting a cat on one side of the y pipe befor they merge, is as Spock would say "illogical".
I can see the inspector being just plain confused then if he looked at it and saw that, then yes i can even side with the guy saying you need either 2 cats, or 1 cat after the Y pipe merge. Either way you go you should look into cutouts befor the cats to get max power at the track (if you go)
I can see the inspector being just plain confused then if he looked at it and saw that, then yes i can even side with the guy saying you need either 2 cats, or 1 cat after the Y pipe merge. Either way you go you should look into cutouts befor the cats to get max power at the track (if you go)
Thread Starter
Launching!
Joined: Feb 2010
Posts: 246
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From: Houston
I suppose that is my fault, I thought there was a law where the cat had to be in the stock location so I had it welded in on the passenger side.
Regardless, I am still seeking some information on a good budget friendly aftermarket cat which will:
1.) meet the mechanics requirement
2.) is small enough to fit on the driver bank of the y-pipe
3.) cut down on exhaust gassy smell.
4.) budget friendly
Thanks!
Regardless, I am still seeking some information on a good budget friendly aftermarket cat which will:
1.) meet the mechanics requirement
2.) is small enough to fit on the driver bank of the y-pipe
3.) cut down on exhaust gassy smell.
4.) budget friendly
Thanks!
If you do 2 they need to match, But 1 moved farther back would be easier and cheaper.
Random technologies has good cats, i would try them, not sure on prices though.
Magnaflow has some for ~75$ as well.
Catco is about the same.
It looks like most of them are like 13-15"s long. random techs might be shorter?
Are you running emissions headers and the AIR pump still?
Random technologies has good cats, i would try them, not sure on prices though.
Magnaflow has some for ~75$ as well.
Catco is about the same.
It looks like most of them are like 13-15"s long. random techs might be shorter?
Are you running emissions headers and the AIR pump still?
Thread Starter
Launching!
Joined: Feb 2010
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From: Houston
No, emmissions equipment all blocked off.
Thoughts on this one?
http://www.summitracing.com/parts/MPE-94026/
I can't remember if the y-pipe (PS) is 2.5 or 3 inches.
Thoughts on this one?
http://www.summitracing.com/parts/MPE-94026/
I can't remember if the y-pipe (PS) is 2.5 or 3 inches.
Last edited by LarsV8; Jul 11, 2011 at 09:05 PM.
TECH Fanatic
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From: South Dakota
Thread Starter
Launching!
Joined: Feb 2010
Posts: 246
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From: Houston
I'm running a pair of Random Technology 100 cell / in. race cats. They made the fuel smell disappear as well as made the inspector happy. In NC we don't do emissions testing for pre-OBDII cars, we just have to retain factory emissions equipment, though most LT1s can get away with no AIR or EGR on the visual. That being said, Random Tech's catalyst materials are quality metals, work very well and make the cats fairly expensive (platinum, rhodium, palladium, etc.). Expect about $200.00 each. You'll probably want to run a pair of 200 or maybe 300 cell per inch cats. Give them a call. I talked to them and found them to be very helpful when I made my decision. I'll bet they have a customer or two that has passed TX sniffers with a similar setup to yours and can tell you what you'd need to pass, preserving maximum power...
AND... metallic substrate is what you want, not ceramic. A pair of Magnaflow 300 cell/ in. at $95.00 each may end up being your solution. They don't flow as good as RT cats but would work for you.
AND... metallic substrate is what you want, not ceramic. A pair of Magnaflow 300 cell/ in. at $95.00 each may end up being your solution. They don't flow as good as RT cats but would work for you.