Rattle, what is this rattle? Options

[Euphoria]

Hey, had a rattling problem somewhere in the exhaust recently which I believed was the flex pipe, had it replaced and the noise is still there so I'm fairly sure its the cat, now as far as I can see in the Australian ST204 there is only one cat which is on the manifold? so I looked up on Ebay and they seem the most expensive ones and as for getting them in Australia I'm sure they are super expensive so I have a couple options.

I looked at my friends mums celica recently and noticed it had headers and where my cat was, it looked to have none and the o2 sensor was lower, why is this? would there have been a cat in there that couldn't be seen perhaps?

another option is perhaps gutting the cat until I find one at a wreckers or something, I've heard people say this lowers power and makes it louder, I've also head it makes it no louder and no more or less power, whats really the answer?

thanks, this is driving me crazy.

This post has been edited by Euphoria: Apr 12, 2010 - 11:30 PM

[Euphoria]

Well guys a couple weeks ago I took my cat off and shaking it around had no noises and it looked in good shape both ends, tapping it with things it didn't rattle.

as that wasn't the culprit I didn't gut it as Id rather a car that was good to the environment rather than getting 0.2hp lol

Put it back together and the noises are still there, only now its at different revs, VERY WEIRD.

The only thing I could really point out was the Gasket between the cat and manifold which was in 3 parts, looking at this diagram below 25576 is the part I'm talking about, mine was in 3 parts that seemed to sit together.

Anyway this is the rattle?