I have a 00 b18c1 in my 94 cx hatchback, i have a 2.5 b-pipe for it and was wondering what kind of cat i should use, the b-pipe has a 3 bolt flange to bolt up to the cat.

 

personally i'd go with the Carsound 2.5" high flow cat. i used that with my B18C1 and JDM DC headers in my 5th Gen. hatch. about $115 shipped to my door new with the flanges welded on and the hardware too. that was from testpipe.com. i have no complaints at all, it works very well.

 

The carsound is a nice part, that'd be my choice for a high-flow cat on a daily driver. Get a test pipe if it's a track only toy.