the flange on my cat has corroded away, any ideas on what to do ??

[RetroPug]

Tom is right, just weld it back together and build up the thickness with some good beads, I did this to my cat as its an o.e item and its hard to get replacements for decent prices.

if its really rotten you can buy flanges on ebay that have 3-4" of pipe attached that you could weld to the cat after chopping the remains of the original outlet pipe off.

I've got the same problem, I've got about 3/4 of a flange and it gets sealed with exhaust paste but it inevitably begins blowing and losing me midrange and making a lot of rasp right underneath me after a while.

If you're not sure what to do yourself I'm sure if you took it to an exhaust fabricators they could cut most of the outlet pipe off and weld a new one on and make a flange for you. It shouldn't really be particularly expensive either. I plan on doing this as I don't have a welder, but it's the faff of taking there that I've been putting off rather than cost.