I have a 1997 Honda Civic LX sedan with a pretty much stock exhaust. The exhaust manifold has a crack running down the center of it to the O2 sensor which I read online is a common problem. I would like to replace the stock manifold with 4-2-1 exhaust headers and a new catalytic converter (as the current one is old and rusting). My problem is that the D16Y7's exhaust manifold and cat are one piece and I'm concerned that if I use aftermarket headers and cat that it will not fit right with the stock resonator pipe and muffler. Does anyone know if moving the cat to the underside of the car like this will cause space issues? I know this is an issue for hatchbacks of the same year but don't know if it will be a problem with my LX. I need to have a cat to pass emissions tests. Anyone done this?

 

You can relocate the cat with a new header/exhaust setup but make sure you have a bung for the O2 sensor before the cat

 

Agree^

you'll also need to extend the wires should you do that. It's called a header* not "headers" this in an inline 4 not a V6/V8...

 

right, if you use a Y8 style (OE or aftermarket) manifold with your stock B-pipe/mid-pipe it will bolt up, but it's a tight fit and will eliminate the cat. cov. so you won't pass emissions. what you'll need to do is convert to an Y8/EX system. you should be able to reuse the muffler, but everything else will need to be changed out.

so long as it goes in with a Y8/EX B-pipe you shouldn't have any trouble.

hatchbacks are shorter. just buy everything to fit a 4dr EX- manifold, cat. cov., B-pipe and as was mentioned extend the O2 wires to fit the new location.

 

This is simple. Get everything from an EX. Everything you have on your car now has an EX version; header, cat, catback. You want the EX version of these components. I mean everything. Get an O2 wire extender for Hondarpartshero's Ebay store so it's plug and play. I really don't know why this seems to be a difficult concept to grasp.

 

Thanks everyone. Glad to hear I won't have to cut and weld extra pipes (seeing as I don't weld that would cost me a bit). Didn't want to get everything and realize it wasn't gonna fit. Thanks for the replies