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I have been thinking about replacing my stock jap spec cat with a 2.25 magnaflow from N*power to complete the headers+cat back echaust it came with. $170ish shipped + $60-70 installatation by friendly local exhaust shop, doesn't seem so bad to me

Option two, remove current cat, ram heavy round bar through the cat creating a "free flowing" cat, reinstall. $14 for 6pk of favourite beer for drinking whiling tinkering. much cheaper, for now...

MB

Hmm... I don't know how good for the enviroment option two is... Is there anything specifically wrong with your cat? I was under the impression that they aren't that restrictive?

ahhh...a gutted cat would be illegal. This is in victoria at least, not sure about QLD but i feel safe in betting it would be illegal.

madboy wrote:Option two, remove current cat, ram heavy round bar through the cat creating a "free flowing" cat, reinstall.

Bear in mind if you do that, your 'zorst is going to be significantly louder.
I did that as a temp measure when I fitted the NB x-force extractors to my NA. I had to fit a cat-delete pipe whilst I waited for the hi-flow cat to come in.
It was loud and raspy. And as all Mexicans know, I hate loud 'zorsts...

If you do that and are found out, the fine is around $10k from memory.

Strongly recommend NOT deleting the CAT.

Boags wrote:If you do that and are found out, the fine is around $10k from memory.

Strongly recommend NOT deleting the CAT.

Ouch.

fastfreddygassit wrote:

madboy wrote:Option two, remove current cat, ram heavy round bar through the cat creating a "free flowing" cat, reinstall.

Bear in mind if you do that, your 'zorst is going to be significantly louder.
I did that as a temp measure when I fitted the NB x-force extractors to my NA. I had to fit a cat-delete pipe whilst I waited for the hi-flow cat to come in.
It was loud and raspy. And as all Mexicans know, I hate loud 'zorsts...

hmm i hadn't considered the increase in noise level. I don't think i'd want it any louder, its not exactly discrete at the moment

Boags wrote:If you do that and are found out, the fine is around $10k from memory.

Strongly recommend NOT deleting the CAT.

this i had heard of, but i must admit, i have never heard of anyone being fined for it...and to get to the point where QT want to pull my car apart to find compliance problems i reckon i would have to be doing something really really stupid in the first place, which, as a father, house owner and general nice guy i would never do

stevesports wrote:ahhh...a gutted cat would be illegal. This is in victoria at least, not sure about QLD but i feel safe in betting it would be illegal.

oh yes, most deffinatly illegal.

bensale wrote:Hmm... I don't know how good for the enviroment option two is... Is there anything specifically wrong with your cat? I was under the impression that they aren't that restrictive?

Well, i have this funny noise when under acceleration at low rpm, say 2500 to 5000ish where it sounds like the exhaust has a hole in it, i have been told by two different exhaust shops that there isn't one and that noise is probably an echo off the cat. I dunno about you, but i like to know what all the noises in my car are, so when something changes, i know instantly when something is wrong, this sound is bugging the cr*p outta me

MB

madboy wrote:..and to get to the point where QT want to pull my car apart to find compliance problems i reckon i would have to be doing something really really stupid in the first place

all it takes is a loud exhaust and they will have a close look at it. they won't need to pull the car apart, a simple tap on the side of the cat will be enough to tell them that further investigation is warranted.

Fatty wrote:

madboy wrote:..and to get to the point where QT want to pull my car apart to find compliance problems i reckon i would have to be doing something really really stupid in the first place

all it takes is a loud exhaust and they will have a close look at it. they won't need to pull the car apart, a simple tap on the side of the cat will be enough to tell them that further investigation is warranted.

Actually all it takes is a non-contact pyrometer pointed at your cat and the temp the compared with other parts of the 'zorst system.
These are the same things you point at your race tyres to see what temp they are at. I used to use one to see how hot the pool was
Cats get damn hot which is why many are a ceramic or stainless substrate.
A gutted cat will not have the same restriction hence will not get no where near as hot.
There is all in comparison to Fatty's cat which is damn cute and I want to steal it.....

Do you have any specific reason you need to economise? (please don't misunderstand... I'm not judging you or anything)

But I guess if you do the cheapie now you'd still need to get a proper cat in the long run! so it'll just add on anyway

If that doesn't work... can I guilt you with the environmental impact?

Ohhh I assume its an enviroment thing... thus the hefy fine...

So how much does it weigh??

wun911 wrote:Ohhh I assume its an enviroment thing... thus the hefy fine...

So how much does it weigh??

Punched through cat, save 1kg vrs less emission & a hefty fine.

wun911 wrote:Ohhh I assume its an enviroment thing... thus the hefy fine...

correct, i must admit i find it awfully funny how they will fine you 10k for taking the cat off a modern car but still let cars like my 77 Gemini on the road without one.

PUR157 wrote:Do you have any specific reason you need to economise? (please don't misunderstand... I'm not judging you or anything)

hmm house, kid, wife, food blah blah all have priority over my car fund... after thats all taken care of, there is very little left for the 5

PUR157 wrote:can I guilt you with the environmental impact?

hehe most likely not, i shoot cute little bunnies for fun when i am back home on the orchard simply owning a car is a heavy environmental impact. If you really want to break it down, all car owners are doing their bit to help destroy the earths ecosystems

Someone on the forum (Kula from memory) said a cop got underneath his car and tapped his cat to see if it was hollow...

Boags wrote:Someone on the forum (Kula from memory) said a cop got underneath his car and tapped his cat to see if it was hollow...

well, tell the truth i was only contemplating pushing say a 20mm hole through, not gutting it completely, I must admit i don't really know if that's possible because i think the substrate inside is pretty brittle.

Let me also state, I am still only contemplating...i am still weighing up the risk vs benefit