Hi wondering if anyone knows if I can get these bolts on the catalytic off? They look welded on for some reason. Can I grind them off with some kind of Dremel attachment since I can't really fit an angle grinder down there. I really do not want to be buying new cats to be able to join these two pipes together again

 

I was able to knock those out in 2 seconds with an air hammer, and then just use stainless nut and bolt hardware to bolt it all up.

 

Thanks for confirming they can be removed. Unfortunately do not have an air hammer, but it means a mechanic that does can do that if willing.

 

If your lucky maybe you can get it out with a hammer, torch and some PB blaster. But yeah, a mechanic should have the tools to knock that out easily.

 

They are studs welded onto the flange. Try grinding the head down and then wacking the other end of the stud with a 3lb hammer.

 

Got it fixed today, cut off the bolts flush on one side, grinded off the head on the other side, torched the area around the remaining pressed in bolt piece, and finally punched it out with a hammer and punch. new bolts on there, car sounds quiet again.

Thanks everyone!