If you have a 216/235/261 exhaust manifold that one or both ears that the exhaust pipe flange bolts to are broken off it can be repaired. First, keep in mind that it isn't that hard to find an unbroken one so use your own judgement. To repair grind all the way around the old flange at a 45 degree angle and down to grey cast iron. Next use the pipe flange as a template to trace a profile onto a piece of 3/8 plate and also mark the bolt hole locations. Cut this out of the plate along with the exhaust hole in the center, drill the bolt holes to 21/64 and tap with a 3/8-16 tap. Now hold this against the old freshly ground cast iron flange and weld it into place. We used to use the TIG and stainless filler rod but have found the MIG with plain old wire works just fine. We bore the exhaust hole in the center of the 3/8 plate slightly undersize and finish out with a ball mill so a donut gasket seats well but a donut will seal in a square cut hole or you can use a flange that takes a flat gasket like an Olds or 265 chevy V8. The couple we have done were on split manifolds where they had a few bucks in them so it was justified. It probably isn't the best way unless you have the machines or access to a brother-in-law type deal but, it does work well.
Thank You MASTER ! As usual Evan has the inside skinny on doing a thing the right way . Any chance of pictures ? .
