what are you talking about?????????????????why would you hollow out a cat ?????

 

are you kidding? well for one thing, its illegal but here in america, we dont give a damn....and the other is to reduce the restrictions the cat put on the exhaust which can back up into the engine and reduce the hp your car makes....when you hollow out a cat you make it easier for the exhaust to leave the car and therefore increase the efficency of your car and boom you got one badass civic...not only does it have more hp, but it will be loud as crap