Matching up Cat inlet to Header outlet (need outlet size for HHC5013 header)
 

Before I go ahead and buy my cat, I was wondering if it would match up to the outlet of my header. I have a DC Sport DCS-HHC5013 4-2-1 ceramic header, but I don't know the outlet size. I want to get a cat with a 2.5" inlet, but I don't know if it will match up.

So.... Does anyone know what the outlet diameter is of my header and if it will match up with a 2.5" cat inlet? Thanks.

1996 Civic Si, d16y8

There is a DC 4-1 with a 2.5" outlet but I think yours is the 2" outlet. A 2" will fit a 2.25" cat BUT your flanges might not line up. I'd take a measurement of your flange bolt locations and size, then buy the cat from that. I ended up selling my 2.25" ID outlet ITR header, because it would bolt up to my stock cat (2") Duh. The biggest problem was the flange. Measure twice and be sure.