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Cheap Hi-Flow Cat

50FFT

By 50FFT,
in Queensland

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predator Grand Master

predator

Posted
Posted

lifespan of a cat is about 5 years, after that they become useless.. and can actually impede flow.

Sure, they might *look* fine, but the honeycomb material is involved in a chemical reaction in converting the CO (and whatever other chemicals it is engineered to attract).. once its spent, no more cat reaction = cat useless..

The Dan Grand Master

The Dan

Posted
Posted

yeah, so then you come to me and say "hey Dan, can you buy me one of those super dooper cat's from your work for $170?"

And I say sure...no problems.

You could go the ultra high flow cats which are now available. They are around $240 and flow an extra 40% or so. They are a much larger body though so you have to be aware of space for it.

SmoothLine Grand Master

SmoothLine

Posted
Posted
You forgot Step 6. Get pulled over by transport inspectors who tell you your cat is hollow because of the poisonous gases bellowing out the back

and Step 7. Get fined up to $5000 depending on how 'aware' you were that it was hollow.

If you have the cat casing still on, but just hollow, you can only be fined for emissions...

I know a guy with a hollowed cat, you cant see the gasses coming out, it has to be taken to an inspection station for a test to concluded that, even then see above.

and the fine is on a per cylinder basis AFAIK.

:D for a uselesspost.

Back on topic: The gain from a highflow cat would be VERY minimal maybe 3rwkw max...

The Dan Grand Master

The Dan

Posted
Posted

haha. They can actually do a gas analysis on the side of the road. And with one of those, you can tell if there is no material in the cat. Your Nitrous Oxides would be through the roof. And as for that, once they find that your cat is hollow....coz any idiot can tell the difference with an analyser, you get a machinery and they fine you. The fine is up to $5000 depending on your involvement.

Thankyou for wasting my time for having to explain it. ;)

BelGarion Grand Master

BelGarion

Posted
Posted

put your hands around your neck and squeeze tight, now try and breath out....

same thing in your exhaust, you totally have defeated the purpose to having a highflowing exhaust, especially if you have the original cat which is more than likley blocked having had a high fuel load dumped into it over the years as well as heat which is associated with running more boost.

mine the front side of it melted and was practicly completly blocked when i last replaced it.

BelGarion Grand Master

BelGarion

Posted
Posted

also if your planning on gutting a cat just bear in mind that the contents of the honeycomb is reportedly carsonogenic (sp?) (that said you can get cancer from scratching your armpit these days so why worry eh?)

i got my replacement cat from batmbl as well, he was very good to deal with.

BelGarion Grand Master

BelGarion

Posted
Posted

as gordon said before, after 5 or so years they are useless, the fronts become melted and blocked and the honeycomb is no longer effective, replacing it with something capable of flowing more and converting more gas is a much better investment than replacing it with another stocker

Tigger Collaborator

Tigger

Posted
Posted

Im not exactly sure what size my cat-back exhaust is... the previous owner told me the spec of it but i forgot... what i do remember is that its bigger than 3 inches... its either 3.25" or 3.5"...

Now the question is, will have to find a cat with the same size ends? Or will standarad 3" hiflow cat do the job? I just dont wanna end up buying a cat that doesnt fit, or even worse, going to a muffler joint to get them to measure it and find out after paying them $$$ that it would have fitted!

The intuitive response would be that the same size cat would be required but im asking bcoz currently with the cat back exhaust, the bigger exhaust pipe is attached to the smaller stock cat... If you get what i mean...

Also, is it possible to put your car up on a jack and replace the cat yourself with some backyard tools? Is it a complicated process?

Anyway, any help much appreciated!

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