I have a few stovebolt manifolds that have one of the ears for the exhaust pipe attaching studs broken off, but with a properly functioning heat riser valve. Simply trying to weld a stud into place usually doesn't work very well, but I think I might have come up with a better fix. How about fabricating a flange from 1/2 inch steel plate, and attaching it to the existing flange by brazing or nickel-rod arc welding, and threading replacement studs into the new flange? The repair part could either be machined for a flat gasket, or tapered for the newer style donut gasket, depending on which type of seal the engine builder chooses to use. A pretty competent welder could add a second flange and a blockoff plate between the front and rear exhaust ports to duplicate the scarce and expensive "Corvette" twin pipe exhaust manifold at the same time. Comments?
Jerry

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