On my way to Marcarl's this spring, I ran over something that did a job on my exhaust collector (on the highway at 70mph). Ended up with two fairly large holes on the botom, one with a large dent. Carl tried a patch but that did not hold. I tried more patching with some muffler cement and again, the heat and pressure blew holes in the patch areas.
Any reason why I can't weld a patch in place? How important is it to try to straighten out the indent before patching? All comments appreciated!