Don, Did you drill out the relief port in the new casting when you did yours or decide to leave it blocked? I remember back when the major BTV failure discussions were going on Fred said he had found some rebuilds that had apparently been done by a well known rebuilder with the relief port filled with silicone. It would be really interesting to know when or if Bendix started blocking the port and whether the later versions had done something different with the seals so as not to need it or if the undrilled casting was someone elses idea.