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Cat removal?* by Oolab1
Started on: 07-27-2014 02:21 PM
Replies: 20 (302 views)
Last post by: Oolab1 on 08-01-2014 03:10 PM
Oolab1
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Report this Post07-27-2014 02:21 PM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
So long story short I recently got the idea in my head to make my stock '85 2.8 a little louder than it already is by either removing or gutting the cat. I've done lots of looking and researching about this but haven't found much useful information. I know it's been brought up before but I was wondering if anyone could explain exactly how to either gut it or remove it completely?

Also if there are any negative consequences of this what would they be? Backfiring is the major concern I have right now as I think it already does. The previous owner drove it around a while back when i was visiting and said that the popping sound was because I had popped a hole in the cat and it was backfiring. However it only makes the sound occasionally when I shift or release the gas at highish speeds so I'm not sure if he's correct. If he is right though would removing the cat fix this or make it worse?

And I before someone goes and says to just get a new high flow cat or that it won't do me any good I would like to point out that I'm about to head off to college next year and can't afford a new anything, but yes I am dead set on doing one of the two if it doesn't damage the car.

*Disclaimer: i am aware of the legal issues involved, but here in Ohio my baby is considered to be a classic car and so no longer has to pass emissions
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dobey
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Report this Post07-27-2014 02:51 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
The backfire could be due to an exhaust leak, yes. Gutting or removing the cat won't necessarily fix it or make it worse. It depends on where the leak actually is. You need to find and fix that.

As for legality, whether or not your car must pass an emissions test is irrelevant. Federal law states it must be here, as likely do state and local laws. If your car has the original cat on it still, it's likely "gutted" already anyway, as the pellets in it would have disintegrated by now.

Removing/gutting it can result in unpleasant exhaust fumes, as there won't be a cat in the system to burn the extra fuel that wasn't burned in the cylinder.

If you just want your car to be a bit louder, then the best solution is to get a different muffler. Replace the original cat with a new one that flows better, install a muffler like the Spintech or such. Or install a full cat-back system. Headers and a better Y-pipe (for the 2.8) would also help, or porting the stock manifolds/y-pipe to remove some obstructions can help the flow as well.
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Oolab1
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Report this Post07-27-2014 04:27 PM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok I'll get on finding that leak asap.

Thanks for the clarification on the laws. That might have been a pretty sticky situation otherwise... even still I doubt anyone will be checking me for anything like that if I'm not getting emissions checked.

I would prefer not to have to buy anything new, but I will if I must. Thanks for the suggestions. I'll head over to the local junkyard first. They have an old Fiero or two that I can probably scavenge a new-for-me muffler or exhaust pipes off of.
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Report this Post07-27-2014 07:28 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Why not just buy a new cat? You can get a univeral clamp-in or weld-in cat (the stock exhaust doesn't have a bolt-in cat), for around $50 on eBay. A quality universal Magnaflow high-flow cat might be around $80.

You probably won't find a good cat very easily in the yard. They tend to be one of the first things to go, as the metal inside (platinum) can be pretty valuable. You might get lucky and find a good aftermarket muffler on a Fiero if one's there that has had a nice system put on it. But be wary of mice having made it their home. They really like mufflers for some reason.
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fireboss
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Report this Post07-28-2014 02:10 AM Click Here to See the Profile for firebossClick Here to Email firebossSend a Private Message to firebossEdit/Delete MessageReply w/QuoteDirect Link to This Post
YAY!! a cat thread...These always end well
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Oolab1
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Report this Post07-31-2014 09:49 PM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
UPDATE: So I was just gonna postpone the decision for a while until I got the car repainted. That was gonna take all my money because I literally have no money in my wallet. Like it's empty. And my bank account is strictly college savings only now. HOWEVER my workplace is right next to an AutoZone, so I stopped in there to browse after I picked up my paycheck today. And in the exhaust aisle I found a new glasspack for $25 and clamps for $2 each. With my new money I bought them and went straight home to install it. Sadly I only got the old stock cat removed before I had to call it a day, but I thought you might be interested to know what the inside of a 30-year-old converter looks like! Sorry for the links but my phone can't post actual pictures. The last one is the inside of the cat. Sadly I don't think I can steal any valuable metals out of this one...
https://www.dropbox.com/sc/...wXHOVISEKUmYE_t0NPJa
https://www.dropbox.com/sc/...TuALr87r328M1iJd_WAa
https://www.dropbox.com/sc/...N507kaTen-mjaPUzF4Va
https://www.dropbox.com/sc/...3Lrm8jf27xVcVejVzBIa
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Report this Post07-31-2014 10:03 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yeah, your cat is already hollowed out because all the pellets disintegrated. So replacing it with a glasspack will probably just make it sound awful.
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Oolab1
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Report this Post07-31-2014 10:05 PM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Why? I mean I get that no cat makes it sound louder and worse but I thought glasspacks were supposed to make it sound better than most cats?
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Oolab1
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Report this Post07-31-2014 10:21 PM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
I guess we'll see. I just went by the AutoZone again and the magical giving bush delivered to me a free exhaust pipe that someone just left there! It's really long so if the glasspack doesn't work out I can easily just switch out the pack to a straight pipe and find some other use for the pack. I can't return it because I may or may not have ripped the box in half and used it to lay over the gross oil spill under the car while I was working... oops :P
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Report this Post07-31-2014 10:27 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
No, glasspacks generally sound pretty awful.

It will probably be loud, raspy, and sound somewhat like you have an exhaust leak or two.

I'd recommend a new high flow universal cat instead.
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Oolab1
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Report this Post08-01-2014 12:33 AM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Mk well I'll look into it but it sounds $$$. Any particular recommendations?
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Report this Post08-01-2014 08:47 AM Click Here to See the Profile for cam-a-lotSend a Private Message to cam-a-lotEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Oolab1:

Any particular recommendations?


You have already received a good recommendation several times, which is to replace it with a new catalytic. They are dirt cheap, keep the air clean , and get rid of nasty unburned fuel smells, which the car behind you will appreciate. Glasspack instead of a catalytic is a good idea for a highschool student craving attention and dying to be noticed, but it really won't create a pleasant sound. I suppose "nice" sound is entirely subjective, much like scoops, spoilers, paintjobs, and such.

[This message has been edited by cam-a-lot (edited 08-01-2014).]

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css9450
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Report this Post08-01-2014 11:28 AM Click Here to See the Profile for css9450Click Here to Email css9450Send a Private Message to css9450Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Oolab1:

Any particular recommendations?


Buy this:

http://rodneydickman.com/ca...th=51&products_id=85

You can install it yourself, no welding necessary and the new one is already sized correctly with the correct diameter tubing. It bolts on with clamps.

And although I don't see them on his site, he had lanyards at one time a couple years ago. Ask nicely, maybe he still has them.
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Report this Post08-01-2014 11:35 AM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by css9450:
Buy this:

http://rodneydickman.com/ca...th=51&products_id=85

You can install it yourself, no welding necessary and the new one is already sized correctly with the correct diameter tubing. It bolts on with clamps.

And although I don't see them on his site, he had lanyards at one time a couple years ago. Ask nicely, maybe he still has them.



Wow, I didn't know Rodney even had that. And people moan about how expensive cats are every time this subject comes up. That's cheaper than a freakin battery, and will last 10x as long on a properly running and maintained car.

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edfiero
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Report this Post08-01-2014 12:25 PM Click Here to See the Profile for edfieroClick Here to Email edfieroSend a Private Message to edfieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by css9450:


Buy this:

http://rodneydickman.com/ca...th=51&products_id=85

You can install it yourself, no welding necessary and the new one is already sized correctly with the correct diameter tubing. It bolts on with clamps.

And although I don't see them on his site, he had lanyards at one time a couple years ago. Ask nicely, maybe he still has them.


Rodney's got a lot of good stuff, but I'd stay away from this. I bought it, and after a year it started rattling like a brick in a coffee can. Got no love from Rodney. Goodbye 100 bucks, hello straight pipe.

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Report this Post08-01-2014 01:09 PM Click Here to See the Profile for css9450Click Here to Email css9450Send a Private Message to css9450Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by edfiero:

Rodney's got a lot of good stuff, but I'd stay away from this. I bought it, and after a year it started rattling like a brick in a coffee can. Got no love from Rodney. Goodbye 100 bucks, hello straight pipe.


Actually, I heard someone in person complain about theirs too.

I can't complain about mine; its been on there since 2003 and its solid and quiet, no rattles.

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Report this Post08-01-2014 01:47 PM Click Here to See the Profile for vwaltdogClick Here to Email vwaltdogSend a Private Message to vwaltdogEdit/Delete MessageReply w/QuoteDirect Link to This Post
This spring my cat clogged so bad the car broke down and I had to get towed home. I went ahead and bought the straight pipe from TFS and the muffler from Rock Auto. It may be because I'm old but I am not happy with the sound of the exhaust with no cat, and the smell can be overwhelming. This winter when I pull the engine to fix the rear main seal leak I will also be installing a cat.
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Report this Post08-01-2014 02:01 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by vwaltdog:

This spring my cat clogged so bad the car broke down and I had to get towed home. I went ahead and bought the straight pipe from TFS and the muffler from Rock Auto. It may be because I'm old but I am not happy with the sound of the exhaust with no cat, and the smell can be overwhelming. This winter when I pull the engine to fix the rear main seal leak I will also be installing a cat.


If you've got a hacksaw, file, socket set, and a floor jack and jack stands, I'd just install the cat now, unless your exhaust is rusted out or something. With that kit from Rodney, and a few hand tools, it'll take less than an hour to do. Then you can at least enjoy your car more until you get around to doing the rear main seal.
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Oolab1
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Report this Post08-01-2014 02:46 PM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Haha but that's exactly what I am: a highschool student looking for attention and wanting to be noticed.

Thanks for the suggestions. I'll keep them bookmarked for when I can afford a real converter, but right now a $25 glasspack is much more affordable for me than an $80 cat. Anyways I just finished installing the glasspack just now, and although I'm sure a real cat might sound better, this thing sounds really good to me. I mean I really like the sound a lot more than before, so I think I'll keep it on for now. It did lose a little power, but since I rarely go over 45 and I don't plan on racing anyone I'm fine with the trade-off.

Also I located that leak in the system that was responsible for the backfiring.
https://www.dropbox.com/sc/...kTpchJNXxJJXrfaDhCna
https://www.dropbox.com/sc/...sZ_8u0l8NGy_QkB8VVLa
You can see why there was a little problem haha.

[This message has been edited by Oolab1 (edited 08-01-2014).]

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Patrick
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Report this Post08-01-2014 03:04 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Oolab1:



You can see why there was a little problem haha.


Was that a close encounter?
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Oolab1
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Report this Post08-01-2014 03:10 PM Click Here to See the Profile for Oolab1Click Here to Email Oolab1Send a Private Message to Oolab1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Oh yeah. A very close encounter. With a dangerous cat. My neighbors feral cat named Ripley to be exact. I was laying helplessly under the car when it walked up and started crawling towards me menacingly. Those tabby cats are scary things man...

[This message has been edited by Oolab1 (edited 08-01-2014).]

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