Found out my stumbling (hesitation, clinking sound) upon acceleration was coming from a clogged catalytic converter. I've already bought a new one to put on. The rear portion of the exhaust slid off pretty easily, but the front is being a bear. I've heard many people say to just cut it out and slide in a straight pipe. My question is this. Since the back end of the catalytic converter is loose, what kind of problems would you have if you just chipped out the rest of the honeycomb and blew it out and then hooked the exhaust back up. My thinking is that it would cause an airflow problem in the exhaust, giving it a swirling effect going through the empty cat. Should I go ahead and try to finish getting the old cat off and replacing? Or has this been done without many ill effects on performance.

 

You already have the replacement cat. I wouldn't just hollow it out as it will be a restriction. That said, doing anything but replacing it is against federal law in the US.