RTV as muffler patch?

I've used RTV for collector gaskets, so "I guess" it will stand the heat. You will have to grind down to some clean metal, and wait probably "a couple of days" for it to fully cure. "It's worth a try."

My "hated Olds" has a huge big sheet metal wrap around the muffler. If I remember right, the muffler for that damn thing is not my idea of 'cheap'