I just got my Random Tech catalytic converter for my 2001 GS-R and it has 2 holes for the 02 sensor. The holes are before and after the cat. My question is that my stock cat just has one hole in the middle of the cat. The diagram says something about a plug but nothing else came with it. Anyone have a clue? Thank you.

 

there should be a bolt that you can put in there. if not try hardware store mebe and use some loctite to hold it in there

 

Which one do I block out? The one near the header or the one going to the exhaust. Thanks.

 

Block out the one near the header

 

Tell me the results of the "butt dyno" after you finish the install. I was thinking about getting one.

 

those cats suck dude. I have one on right now and I'm about to change it. after the 2-3 day after I bought mine, everything started to rattle. it's works well though, you can feel the higher RMP pull from the more high-flow, but still, in my opinion, still not worth it since I've been hearing negative comments about this cat rattling from other people too.