While looking at the underside of my 1990 GL, I noticed that, right behind the cat, the header pipe is seriously dented.  It looks like someone backed into something, and I would estimate that the pipe is bent in on the one side by about 60-70 percent of the total diameter of the pipe.

This would cause a significant loss of power, right?  Would it be possible to drill a hole, slide-hammer it out and weld the hole, or am I better off installing a new header pipe?

John Haddad