The si I just recently got has hks hi power exhaust on it with 2" piping. The cat was hollowed out so im replacing it and thinking of getting the magnaflow cat and im also getting dc sports stainless steel 4-1 header. Do I need to get a flex pipe or will the header and cat meet directly and not give me enough room for one? Also, does anybody know if the cat comes with the flange that connects to the header that has springs and bends or do I have to get a flex pipe? Thanks.

 

This one is for Calif. http://www.magnaflow.com/02catalytic...irectfit=46628
And yes the DC Sport header and cat meet directly or you can get one without the flange.; http://www.magnaflow.com/02converters.asp A cat without the flange you could do a custom install with flange on one end of the flex pipe to the header.

 

So a cat with the flange on one end to connect to the piping and then a flex pipe welded to the cat and a flange on the other end connecting to the header? What size flex pipe would I need? The piping is 2"

 

Cause im pretty sure the cat dont come with the spring loaded flange so the exhaust cam move without causing cracks. Or does it?

 

I have had my DC Sports 4-2-1 header connected to the stock Cat. (flange to stock spring loaded flange) no flex pipe for 7 1/2 years and over 83,000 miles and NO cracks, and that is with stock motor mounts (lots of movement).
Take a look hear; http://www.hondaautomotiveparts.com/...5=EXHAUST+PIPE
If it was "me" i would buy Part #20 /1ea. #21 /2ea. #23 /2ea. #33 /2ea. and be done with it. but maybe someone out there has a better way to do it.?

I hope this helps.

 

since when did a HKS hi-power system come in 2'' piping, that's smaller than stock on the Si....