I know on my xj I got it with a magnaflow cat and my dad says that the cat that is on there is a cheap one that the last owner put on and that is one of the reasons why it failed it's inspection last time. I was just wondering if my dad was right that the original cat is much better than the magnaflow cat?

 

I would say the Magnaflow would be the better cat.

You should have been given a piece of paper with your trucks stats. Post up your numbers, we'll tell you why you failed and what you can do to fix it.