If I empty or remove the Catalytic converter, would it hurt car performance?

you would be violating federal law by doing either. whay dont you just fix it if you are having an issue?? what is wrong with the cat?? you have a 5 yr 50k warranty on it.

Roy

apart from above, performances would also be affected as the Os esensors aould show abnormalities and the PCM would be commanded to set standards for certain operations.