Here's a follow up to this old post. My fix detailed above worked. I now have over 25,000 miles on the setup with no exhaust leaks.
A clarification on the procedure: when I stress relieved the pipes I heated them about a foot away from the flanges.
I don't get it. Why not (if possible) machine the bevel in the Fenton header(s) to accept the donut and would all this be a non issue? As explained the donut is very forgiving and allows for angular misalignment while completing a seal.
That would be a great plan if one was starting from scratch. I already had about $500 invested in pipes with flat ends. As Joe stated, one of the Fentons already has a bevel. You would only need one cut. Then have flared pipes installed.
