Kris is right, the car will not pass an MOT now. And there's no way but putting a cat back in to pass it.

when people smash the insides out its only so the mot place thinks there is a cat there, but you also have to weld a pipe inside it. i feel you have just fucked about 300 quids worth of cat and you will now be shafted come mot time cos it will fail emissions badly, unless you have a diesel of course then it makes no difference.

why didn't u just sell ur cat on here, and by a decat pipe??
u probably would have ended up with a bit extra money!

won't make much of a difference but unless you fit another CAT

theres a few hundred quid down the drain :!

I thought i had heard that some where before

Knocking your cat out wont help the performance, possibly reduce it.. The Exhaust gases wont travel smoothly through the system as the hollowed cat will make turbulance... Not a good idea.

the rattle might be down to the new exhaust note your getting it will be allot more raspy, this could be causing some thing else to vibrate

So yesterday i smashed the block out of my catalytic converter out, but now im regretting it, because it kinda rattles. Its not got anything left in it, its just cos its hollow and there's noting to silence the exhaust gases, but is there anything i can do to make it sound better, other than getting a de-cat pipe? Plus, wont this do the same?