So one of my cats went out today on my 08 Z and so im going to get upgraded high flow cats. Where I live emissions don't matter so im mainly am concerned with the sound and HP gain I don't like rasp I want a nice low deep exhaust. Right now im just running the stock exhaust I will be uprading later on. Does anyone have a preference on high flow cats?

 

High flow cats are so expensive, if you don't need to worry about emissions, for a little more you can get ART pipes which will sound good and perform much better than HFC which are still somewhat restrictive.