Removing Cat and centre muffler in ae101 - worth it?

[~SlideWays~]

The ms's Trueno has done about 150k's now and I'd assume the cat has never been touched (probably clogged up), I was under it the other day and thought it'd be pretty easy to remove that whole Cat and centre muffler then weld in a straight pipe.

First of all, will this cause wof issues?
Second of all, would it be worth it?
Thirdly, since the O2 sensor is right before the Cat - is it likely to be negatively effected because it may not get as hot?


Cheers

[ezy10s]

dunno about the negative effects of removing both those item but it will sound like shitey. tinny horrible noise usually results when people have removed them

[rolla_fxgt]

perhaps just take the cat out & gut it & put it back in, won't be a visable change & it shouldn't change the sound too much (someone correct me if I'm wrong)

[xsspeed]

would think the sound will still change if you just gutted and refit it.

If you wanna get rid of it, I would stick a small muffler or hotdog in its place (assuming its in the horizontal section of pipe as I havent been under my ae111 yet) that should help remove the drone.

I'm not sure on the legalities/requirements of removing your cat is though, someone else will know for sure

[1I1]

At the start of the year i had a local exhaust centre remove the cat from my AE111 so it was just 60mm exhaust with a resonator and a turbo flow style muffler.... it sounded crap!! i then had to spend another $90 to get a coby muffler installed which made it sound 10x better. As for gains (car was at 95,000) i didn't see big gains - hell don't think it made too much difference at all

I think it's ok at the moment regarding legal requirements but i wouldn't be surprised to see them become compulsary if oe

[~SlideWays~]

Hmm maybe I should take it off and see how hard it would be to just gut it, the ms's wouldn't be too happy if her car sounded horrible afterwards though...

Guess the best bet is fitting a resonator in place of the cat and standard little centre muffler.

Hopefully it'll liven it up a bit because its feeling quite choked these days.

[matt dunn]

Hmm maybe I should take it off and see how hard it would be to just gut it, the ms's wouldn't be too happy if her car sounded horrible afterwards though...

Looks easy to gut them, but it is not.
And once you start you have to go the whole way.

Can be done but takes quite a bit of time to chip it all out if you dont want to cut it open and reweld it.

[RomanV]

Just pull it out, and see if you can see through the cat, or if it's all blocked up.

If it's looking like a mish mash of crap, get a muffler or whatever welded in its place.

Gutting it is like having a 2" exhaust then 4" exhaust then back to 2" exhaust... More of a restriction to flow that way than a cat converter that works properly and/or isnt clogged.

I dynoed 0hp difference between cat converter and straight through pipe.

[dirty1]

I have just had to gut the cat in my 3s-ge. it didnt make too much difference in the noise of the exhaust. the cat was as part of the manifold rather than under the car, so it still has two baffles and the muffler.
i used a masonary drill bit on my drill to strip out most of the stuff in the cat. masonary drill bit does not have any sharp edges so it wouldnt damage any solid metal parts of the cat casing. then used a long screw driver and set of pliers to get the rest of the stuff out. it took about two or three hours to get it totally clean.

[DFECTED]

scrap the cat in for $80 at catman in seaview!

[Bling]

Don't fix whats not broken imo. Unless you are REALLY bored or something

I replaced mine with a resonator, but only when the cat dropped its guts and my car smelt like a bad fart after a long drive

As said above, it will sound like absolute ass if you just remove it and replace it with straight pipe. Would want at least to replace the centre muffler with another muffler and the cat with a resonator imo.

[RS13]

I replaced mine with a resonator, but only when the cat dropped its guts and my car smelt like a bad fart after a long drive

Yeah, mine does this really badly, I don't even need to go for a long drive! A couple of 8krpm squirts and it smells like my car is recovering from a 3-day speights bender! Is there something sulfurous inside the cat that gets too hot, or is it that the internals have fallen apart?

[AE82 FXGT]

scrap the cat in for $80 at catman in seaview!

Yeah if getting it taken out, always ask for it back!
They are worth very good $$$, even more that $80

[matt dunn]

I replaced mine with a resonator, but only when the cat dropped its guts and my car smelt like a bad fart after a long drive

Yeah, mine does this really badly, I don't even need to go for a long drive! A couple of 8krpm squirts and it smells like my car is recovering from a 3-day speights bender! Is there something sulfurous inside the cat that gets too hot, or is it that the internals have fallen apart?

FWIW, if the exhaust smells like rotten eggs,

it is because the cat converter is working near perfect,
and the exhaust mixture is near perfect for it to work,


so basically, if it smells like shyt, your car is in great condition.

[Bling]

haha, i'd rather have a car not quite working right than put up with the smell

global warming is a good thing imo anyway

[Jonno2002]

First of all, will this cause wof issues?
Second of all, would it be worth it?
Thirdly, since the O2 sensor is right before the Cat - is it likely to be negatively effected because it may not get as hot?
Cheers

-never had wof issues with passthrough/bypass pipe instead of cat
-i noticed a difference at top end but meh thats prob just me
-as for the o2 sensor if its back that far it will be a heated sensor (3 or 4 wire) and thus doesnt need an external heat source

as for the bad sound of removing the cat, i didnt notice shit all diff either just put a strait pipe in place and rest is still stock, maybe its only noticeable with a fart cannon on the back which you should be shot for having anyway if you do lol

[~SlideWays~]

geez are they actually worth money? sweet!
Good point re being multi wired, thats good to know.
What I'll do is make a flanged section so its easy to put the cat and silencer back in if it turns bad.

man that took ages to type because im on the ps3

[touge rolla]

Hey I could do with some cash, anyone know where in CHCH I can trade my cat with some of the folding stuff?

[Jonno2002]

scrap metal dealers