I'm thinking about ditching the cat.
06-16-2007, 07:53 PM
#1
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I'm thinking about ditching the cat.
I assume that cat on my car is original and I have an exhaust leak in that area.
When I take it in to get the leak repaired I'm considering just removing the cat and having him make a replacement pipe. My concern is how much louder it will be afterwards. The exhaust now is not loud at all, but it does have a rather enjoyable deep sounding loud spot at 2000 RPMs... and only there... and can set off sensitive car alarms... my sons included.
I seem to recall reading here that the cat does offer some noise reduction and someone saying that after removing it the car can get quite loud.
Opinions?
Also after removing it what's done with the O2 sensor?
When I take it in to get the leak repaired I'm considering just removing the cat and having him make a replacement pipe. My concern is how much louder it will be afterwards. The exhaust now is not loud at all, but it does have a rather enjoyable deep sounding loud spot at 2000 RPMs... and only there... and can set off sensitive car alarms... my sons included.
I seem to recall reading here that the cat does offer some noise reduction and someone saying that after removing it the car can get quite loud.
Opinions?
Also after removing it what's done with the O2 sensor?
06-16-2007, 08:19 PM
#2
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Do it.
It's not that loud. It's loud when you are 3.5+k but that isn't most normal driving so everyday shouldnt be an annoyance. I guess it depends what you have for a muffler at the back as well.
O2 sensor is ahead of the cat, you can leave it.
(PS - look out for environmental freaks knocking you.. in 5...4...3...2...)
It's not that loud. It's loud when you are 3.5+k but that isn't most normal driving so everyday shouldnt be an annoyance. I guess it depends what you have for a muffler at the back as well.
O2 sensor is ahead of the cat, you can leave it.
(PS - look out for environmental freaks knocking you.. in 5...4...3...2...)
06-16-2007, 08:31 PM
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I read the title expecting to have something sympathetic to contribute but oh well.
https://rennlist.com/forums/off-topic/358929-kill-the-dog-he-ate-my-homework.html
OTOH it's amazing how long the OE cats last if the car has never run aftermaket chips. I have one I toss on for smog testing that had 140K on it and still works great. The cat that ran Guru chips was dead on arrival at 91K.
A friend came by last night with a fully built late LS-6. He has electric cut-outs on it and with the gates closed it is as quiet as my car, with the gates open it sounds like the high-10 sec. car it is. Wonder what a 951 sounds like with a side dump off the downpipe before the cat?
https://rennlist.com/forums/off-topic/358929-kill-the-dog-he-ate-my-homework.html
OTOH it's amazing how long the OE cats last if the car has never run aftermaket chips. I have one I toss on for smog testing that had 140K on it and still works great. The cat that ran Guru chips was dead on arrival at 91K.
A friend came by last night with a fully built late LS-6. He has electric cut-outs on it and with the gates closed it is as quiet as my car, with the gates open it sounds like the high-10 sec. car it is. Wonder what a 951 sounds like with a side dump off the downpipe before the cat?
06-16-2007, 08:46 PM
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The car has about 240K miles on it and it sounds like the cat is rattling also. I've had a couple of leaks on it brazed and now have another, most likely it's not in the best condition.
To make the greenies happy, I'm barely getting 20mpg from the car now, and I don't drive it hard... it's never gotten over 22.5... I was also hoping that by freeing up the exhaust I will be doing my however small part to help reduce the dependence of this country on imported oil.
To make the greenies happy, I'm barely getting 20mpg from the car now, and I don't drive it hard... it's never gotten over 22.5... I was also hoping that by freeing up the exhaust I will be doing my however small part to help reduce the dependence of this country on imported oil.
06-16-2007, 08:46 PM
#6
You post this thread right when I got set to delete the cat sometime in the next couple of weeks. Still not sure what muffler I'm getting, I've seen waaay too many opinions on that subject.