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Black&Gifted
10-24-2016, 12:05 PM
Had the rear cats removed this past weekend. Went smoothly and shop did a real nice job. Some pics of the process. Was also very impressed how good the car looked from underneath, particularly for being 14 years old.

http://uploads.tapatalk-cdn.com/20161024/8f411323fe065c549710d12e519ef1 c3.jpg

http://uploads.tapatalk-cdn.com/20161024/e55a73e477fc3879b0314e2c13087b 71.jpg

http://uploads.tapatalk-cdn.com/20161024/bfeea930b44265d0bcdec438b9c407 98.jpg

http://uploads.tapatalk-cdn.com/20161024/2b202c30585084d3dba579f4ceaa02 ed.jpg

http://uploads.tapatalk-cdn.com/20161024/304dba2ae6e65045ef8418d4835b42 c8.jpg

http://uploads.tapatalk-cdn.com/20161024/6a3f9074d64ec0a7d3cb38c3e67523 d1.jpg

ctrlraven
10-24-2016, 01:13 PM
A smart tech would of unbolted the back section of the rear cat area, expanded it and slid the new pipe inside for a proper airflow. Having the stock tube inside the new tube creates a lip inside. Not that you would really every notice a difference.

Either way enjoy the increase exhaust noise!!

Ourobos
10-24-2016, 01:54 PM
If they had slid it inside, it would have decreased the overall diameter.. I can't see how one is better than the other for that miniscule amount.. It's not cylinder heads where flow velocity matters..

JustRight
10-28-2016, 10:41 AM
You missed this part of the sentence:

"expanded it and slid the new pipe inside"

BAD MERC
10-28-2016, 12:11 PM
This has been on my mind and I'd like to hear your opinion of the differences in sound or performance. I have Super 40's and delete tips so it's a lot louder than OE already.

Black&Gifted
10-28-2016, 04:48 PM
Exhaust is 100% stock except for this.

On start up and idle, it is a bit louder and deeper. Not piss your neighbors off type loud start up though.

Sound on acceleration is deeper, more throaty and more noticeable. May also be a bit raspier, but if it is, that is definitely secondary to the other sound benefits.

Sound at idle and cruise is about the same or perhaps a hair louder. Haven't noticed any drone either.

For "performance," I would say it is really just more responsive. Gets up and goes "better." Similar to how I'd describe installing a CAI. Doubt there are any true or meaningful HP/TQ gains.


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Black&Gifted
10-28-2016, 05:07 PM
A smart tech would of unbolted the back section of the rear cat area, expanded it and slid the new pipe inside for a proper airflow. Having the stock tube inside the new tube creates a lip inside. Not that you would really every notice a difference.

Either way enjoy the increase exhaust noise!!



Now that you mention it, that would have been a good way. But you're right, not really going to adversely affect an effectively stock NA engine.


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ctrlraven
10-28-2016, 06:05 PM
This has been on my mind and I'd like to hear your opinion of the differences in sound or performance. I have Super 40's and delete tips so it's a lot louder than OE already.
When I first deleted my rear cats I had the same setup. I didn't notice any increased performance since the mufflers are chambered and the stock pipes are small.
Sound increase was nice, wasn't earth shattering but the exhaust note/tone just sounded better, kinda more like you would expect the car to sound like.

https://scontent-lga3-1.xx.fbcdn.net/v/t1.0-9/62504_1271884935767_5798533_n. jpg?oh=c3d4aaec6a9678b915e8656 417869964&oe=58D3A8F4

Mr. Man
10-28-2016, 07:01 PM
Should have had the mid-pipe upgraded to 2 1/4" from 2" while it was up on the lift. That's the choke point in an otherwise fairly decent flowing system on a stock car.

ctrlraven
10-28-2016, 08:24 PM
Should have had the mid-pipe upgraded to 2 1/4" from 2" while it was up on the lift. That's the choke point in an otherwise fairly decent flowing system on a stock car.
Might as well change the whole thing to 2.5" mandrel bent stainless front to back. lol

Black&Gifted
10-28-2016, 10:06 PM
Might as well change the whole thing to 2.5" mandrel bent stainless front to back. lol



And add long tubes and exhaust cutouts lolol


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Mr. Man
10-28-2016, 10:17 PM
Might as well change the whole thing to 2.5" mandrel bent stainless front to back. lolI wasn't aware of his budget, so thinking the OEM flows pretty well the mid-pipe shouldn't cost an arm and a leg. If he has the budget the 2 1/2" system would be ideal. :)

Davco
10-29-2016, 05:40 AM
Exhaust is 100% stock except for this.


I've been debating on doing it for my stock set up. Did you happen to get any before and after vids?

I can't decide on removing the cats or just going with new mufflers. I don't want it to be super loud.

Black&Gifted
10-29-2016, 08:59 AM
Sorry, no vids but I'm sure there are some on YouTube.

Haven't done mufflers on either marauder I've owned, but hearing marauders with aftermarket mufflers vs rear cats removed, the latter is definitely not as loud. Of course, it depends on the type of muffler.


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ctrlraven
10-29-2016, 03:48 PM
I've been debating on doing it for my stock set up. Did you happen to get any before and after vids?

I can't decide on removing the cats or just going with new mufflers. I don't want it to be super loud.
Rear cat removal is cheaper than adding new mufflers. Go with that first. A lot of people are quite pleased with just the slight note increase.

babbage
11-09-2016, 05:42 PM
you changed the bolt locations, so later if you add headers, or wanted a catback it will no longer easily bolt up. also old cats are worth $50 each.

Black&Gifted
11-10-2016, 03:59 PM
Awesome re cats. I kept them after removal.


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Jtrip
11-10-2016, 04:38 PM
I am interested in doing this. What did you pay and what should I tell the exhaust guy I need done exactly?

Also, will my check engine light come on?

Black&Gifted
11-10-2016, 05:38 PM
No check engine light.

I paid $80 and kept the cats. So if I sell them, I should come out ahead lol.

I went to a performance shop that I'm sure does this all the time given their current stable. With them, I didn't even have to say much.

I've have it done on other cars I've owned at small independent (perhaps lesser reputable) exhaust shops and my go to line is "I think there is something wrong with the second set of cats on my car. Can you guys check it out." When car is about to be inspected or put on the lift, I just ask them to remove them. Never really an issue.

Perhaps more than I need to do but there has always been other customers in the shop and I didn't want to blatantly say "remove my cats" in front of them.


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justbob
11-10-2016, 05:46 PM
Muffler shops normally charge $30 total for both around here. They don't give a crap as long as it leaves their shop with one cat for each bank or they risk a serious fine.


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03Merc
11-10-2016, 07:38 PM
http://uploads.tapatalk-cdn.com/20161111/eb169da8f2af13454de171164066d9 0e.jpg

What are cats?

https://vimeo.com/191103442


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justbob
11-10-2016, 07:50 PM
I have those SW off-road extensions in a box somewhere in case of need. I ran catless when I had the MAC LTs and cut outs. I couldn't tolerate the smell. [emoji43]


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Seneca
11-11-2016, 05:21 AM
I have those SW off-road extensions in a box somewhere in case of need. I ran catless when I had the MAC LTs and cut outs. I couldn't tolerate the smell. [emoji43]


Sent from my iThrone using Tapatalk yes the smell does get to be a bit much

Rick@Metco
11-11-2016, 09:43 AM
We deleted the rear cats on Kristi's car, primarily for the improvement in sound. It definitely sounds better, and Kristi's very satisfied.

On the other hand, I'd prefer it a bit louder, so I'd like to delete the forward cats (Lidio's tune, so no CEL), or change the mufflers. But it's her car.

ctrlraven
11-11-2016, 12:53 PM
Resonator delete tips can help as well, they don't increase the sound, more or less just fine tunes the note coming out.