Welding in a Flex Pipe on Cat

[EyExR]

Has anyone ever done this?

I'm thinking about cutting up a regular 325i cat to get the flex pipe off. Then welding it to my iX cat.

This is all because I can not find a replacement...

Thoughts?

[slammin.e28]

You can get just a flex pipe at any good automotive store. Just buy and weld. Easy.

Of course, I'm a lazy motherfucker.....so I'd ditch the cat altogether, yeah.

[jlevie]

You can get an SS mesh type replacement for the bellows type on the down tubes from Summit racing. That is what I used to replace a broken bellows on my Spec E30. Unless you just happen to have a spare head laying around to use as a jig replacement of the bellows will be a pain. You'll need to pull the down tubes, cut out the old bellows, then remount the down tubes and tack weld the replacement in place. Then pull the down tubes to finish the welds.

[EyExR]

You can get an SS mesh type replacement for the bellows type on the down tubes from Summit racing. That is what I used to replace a broken bellows on my Spec E30. Unless you just happen to have a spare head laying around to use as a jig replacement of the bellows will be a pain. You'll need to pull the down tubes, cut out the old bellows, then remount the down tubes and tack weld the replacement in place. Then pull the down tubes to finish the welds.

^ makes sense. because of fitment? I would think, however, that you could just measure it out, no?

I guess my question now is which replacement flex pipe could I use? Is there a standard diameter size on the down tube?