I am replacing my exhaust on a 1990 accord. I couldnt get the cat bolts loose so I torched them off. The resonator pipe then slid off fairly easy.Problem being now that the remainder of the studs seem stuck in the flange. Should they just pop out? tried hitting with hammer with no luck. Any ideas? Are they permanatly attatched? Or should they come out? Any advise would be helpful

 

They should come out. There may be really rusted on there. Probably try cleaning as much rust out with a wire brush where the stud goes through the flange on both sides. Try heating the flange with a torch (don't heat the bolt) then try hitting it with a hammer. An air hammer might be good to try, but I don't know what tools you have.