I have a 97 ek with a jdm itr b18c. If you get a jdm header: I went with the T1R (type one racing) exhaust. It is 2.5" and allows room for a cat. If you get a standard dx/cx usdm exhaust it will be right at the header leaving no room for a cat. The t1r is designed for a ctr and leaves room for a cat. I had a carsound with custom extensions put in, but a jdm itr or ctr cat will work.