I recently bought a new bolt-up cat for my 99' civic Si from nopi. We used all honda gaskets and it still leaks.Sounds like sh!t. It must be a manufacturing defect. They say that its a "magnaflow" cat but it doesnt say magnaflow anywhere on the box.
You would figure a big exhaust company like magnaflow would put their name on the box. I thought i was buying a pretty decent cat. It was only $116, i guess you get for what you pay for. lol. I'm taking it back next week and getting a bolt-up one from advanced auto($197). They are $800 from Honda.
Here is the link to the douche bag catalytic converter.
http://www.nopionline.com/nopistore/...0HONDA%20Civic