my car has a catalytic converter on it and i was wanting to decat it, but i dont want to spend money on a decat pipe just now because cash is streched just now, but i dont want to weld a straight through pipe on because the rust starts at the weld really quickly and the pipes are in good nick so dont want to ruin them. what would be the downsides to just smashing the honeycomb out with a broom handle? would it give any improvement to power/mpg? anyone else tried it? my car doesn`t need one for the mot.