I was wondering what are the ramifications of having a new catalytic converter. I just recently had my downpipe replaced, and was wondering how long it will take for it to be broken in. Also, is there any powerloss untill the cat is broken in? I was wondering if something had to burn off at first before the downpipe will have maximum air flow. And will the exhaust sound very different after the cat is broken in?

Thanks for any help!

 

there is no break in time for a cat. its good to go out of the box.