I was wondering what would be necessary to replace the rb turbo back exhaust system's mid pipe for a bonez 3 inch cat. I know that I would have to order the 3 inch blank cat but what other parts (ie. flanges, gaskets, etc) would be needed and would a custom fabrication be needed?

 

A muffler shop would have no problem doing the fabrication. Just get 2 3" flanges with the correct bolt spacing and you're good to go. You may be able to use the gaskets, but if it's been on there for a while, 2 new ones would be needed. Another thought. I was going to add a converter in front of the silencer. Just cut the dp the length needed and weld in the converter. A lot less fabrication and Random Technologies sees no problem with installing the cat in front of the silencer. You'll just need to shorten the air pipe tube. I'm just not certain as to how much of a restriction the cat/silencer would create, but probably minimal.