Originally Posted by fahr_side
Just wondering if you'd forgotten your statements in this thread
BAC5.2 is right. You can cut the flex section out and weld a solid pipe in there, but that just redirects the force of expansion somewhere else. The header will then crack at the next weakest location, sooner or later. In your position I'd probably just get a better header. If I really, really liked the leaking header, I'd try welding a new flex section into the up-pipe and hope that holds for a while.
I'm well aware of what i said, and well aware of your mockery.
I'll be welding in a new flex pipe.