Cat going bad?
Thread Starter
Lexus Test Driver
Joined: Apr 2003
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From: New York
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.
Lexus Test Driver
Joined: Apr 2004
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From: California
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.
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? 
Thread Starter
Lexus Test Driver
Joined: Apr 2003
Posts: 1,466
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From: New York
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.
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.
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
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
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From: Ok
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.
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; Oct 31, 2004 at 05:28 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.
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.
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
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Joined: Feb 2003
Posts: 80
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From: Ok
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.
Did you get rid of the cats? No inspections in Ok anymore! I am in OKC BTW.
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
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
Rookie
Joined: Feb 2003
Posts: 80
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From: Ok
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.
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.
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.
Peace,
Jonny
Rookie
Joined: Feb 2003
Posts: 80
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From: Ok
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; Nov 2, 2004 at 06:26 AM.
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.
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.
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