[mickmate]

The inside and outside have different rates of expansion. I have seen some break on the inside because of this. Stainless specialties have a nice product and I have used quite a few Classic Chambered (steel) mufflers in Cobra sidepipes. If the pipes are set up on a fixture to keep the front and back parts in line and the mounts in the correct place the muffler can be cut out and a new one welded in. It is really easy to do on the car. The mufflers are short money it's the replacement job that costs a few hours. There are quite a few different options on inside diameters, direction of louvres and with or without packing. Check out the websites of the two mentioned and let us know if we can help with any product advice.