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Cat going bad?

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Old 10-29-04, 10:25 PM
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mrshabo
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Default Cat going bad?

Sometimes when I gun it, I smell rotten eggs. If so what should I do? go to the junk yard and cut out the cat and replace it with a straight pipe or buy another cat. any gains from this? does the car get louder? i like the way my car sounds now.
Old 10-30-04, 03:32 PM
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96sc3
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a straight pipe is louder than a good cat but a bad cat can be louder than a straigh pipe.....
Old 10-30-04, 05:46 PM
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go to the junk yard and cut out the cat and replace it with a straight pipe or buy another cat. any gains from this? does the car get louder? i like the way my car sounds now.
gains from the straighter cat, nothing to filter the emissions so it goes straight out
Old 10-30-04, 10:04 PM
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Well, the rotten egg smell points to your cats. And running without will definitely make the exhaust note lauder, but more importantly, how are you going to pass emissions of you take out your cat? Is this going to be a race-only vehicle?
Old 10-31-04, 01:32 AM
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emissions isn't a problem, i just don't want to change the tone of the car. I like it fine just the way it is. I don't know how my borlas will sound after i take off the cat.


i only get this smell once in a blue which is weird because i drive the car hard everyday. maybe it's someone elses car? or maybe it's just the n.y air lol.
Old 10-31-04, 04:19 AM
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Emissions isn't a problem??? In NY? ....you got PM...
Old 10-31-04, 05:16 PM
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Hey man,

Yes, it will have a small effect on your sound if u put in straight pipes instead of cats. Although not meant to focus on sound, I am sure the inside of the cat does filter out a degree of noise.

I am not 100% on this but I am pretty sure.

I know on my Legend I put in a Hi-flo cat and there was a sound difference. Maybe it was just me, but I am pretty sure there was.

Peace,
Jonny
Old 10-31-04, 05:27 PM
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I don't know for sure about power gains when doing away with the cat but a local muffler shop told me it would be in the range of 20hp. Now at the time he was telling me this I was having the bottle neck Y cut out to go true duel. I assume he was talking about 20 hp. total after taking out the cats and the Y bottle neck. I didn't have the cats taken out though.

BTW,I see on ebay that someone is selling resonators that supposed to replace the cats on our cars. It has a place to put the Oxy sensor in and I guess that would eliminate any loudness from having no cats.I think it would be better than going with a test pipe. The resonators are straight through but offer insulation for sound deadining.


I would also like to know the hp gains for just removing the cats.Someone has surely done this.

Last edited by RTLEXSC; 10-31-04 at 05:28 PM.
Old 10-31-04, 06:02 PM
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Originally posted by RTLEXSC
I don't know for sure about power gains when doing away with the cat but a local muffler shop told me it would be in the range of 20hp. Now at the time he was telling me this I was having the bottle neck Y cut out to go true duel. I assume he was talking about 20 hp. total after taking out the cats and the Y bottle neck. I didn't have the cats taken out though.

BTW,I see on ebay that someone is selling resonators that supposed to replace the cats on our cars. It has a place to put the Oxy sensor in and I guess that would eliminate any loudness from having no cats.I think it would be better than going with a test pipe. The resonators are straight through but offer insulation for sound deadining.


I would also like to know the hp gains for just removing the cats.Someone has surely done this.
Hey man,

I am pretty sure that they meant after everything u did - 20 horse for cats alone is ridiculous!! I kinda did the same thing as yours with my exhaust - Y pipe, removed all resonators, stock mufflers.

Where in OK are you located?? We have about 7 or so that I know of that are in OK so we need to get a meet together.

Peace,
Jonny
Old 11-01-04, 08:48 AM
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I fugured he was talking about 20hp after doing it all. I left my 2 rear resonators on and had them cut out the front ones and the Y.It did increase the hp and the sound isn't loud at all. Sounds pretty good with the stock mufflers on there.
Did you get rid of the cats? No inspections in Ok anymore! I am in OKC BTW.
Old 11-01-04, 01:17 PM
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Hey man,

Cats are still there, but I am considering removing them!! I know it's illegal but how many times do cops get on their hands and knees and check!! That's the good thing about having stock mufflers~~

I have my whole exhaust off right now so this would be a good a time as any to do it. What do u think??

I am in Tulsa so if u are ever going to visit T-Town hit me up.

Peace,
Jonny
Old 11-01-04, 02:18 PM
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I am seriously thinking of taking my cats off to see if there's any gains. I would think there should some hp because those cats have that honeycomb stuff in there that can trap a lot of stuff and get stopped up.
Old 11-01-04, 07:00 PM
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Originally posted by RTLEXSC
I am seriously thinking of taking my cats off to see if there's any gains. I would think there should some hp because those cats have that honeycomb stuff in there that can trap a lot of stuff and get stopped up.
Let me know what u decide man. I have to put my motor back in on Sat so would need to do it before then if I decide to. Look forward to hear ur decision.

Peace,
Jonny
Old 11-02-04, 06:24 AM
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I think I might just go ahead and get some of those resonators to put on in place of the cats.I don't really want to gut the cats because I may want to put them back on sometime in the future. Those are high dollar items. If I were you I would get a test pipe,resonator and keep the cats just in case you ever need to put them back on there.

Last edited by RTLEXSC; 11-02-04 at 06:26 AM.
Old 11-02-04, 10:12 AM
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Originally posted by RTLEXSC
I think I might just go ahead and get some of those resonators to put on in place of the cats.I don't really want to gut the cats because I may want to put them back on sometime in the future. Those are high dollar items. If I were you I would get a test pipe,resonator and keep the cats just in case you ever need to put them back on there.
Hey man,

I already have all my resonators pulled. I guess I will just leave the cats - more trouble messing with than it's worth!

Peace,
Jonny


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