BP2 puzzle

[F3BZ]

i finally got around to disassembling a BP2 from a GT-R. seemed to be more rust than i'd expect on the timing belt pulleys and crank sprocket. when i took off the timing cover back plate (first pic) i see this hole in the head flanked by bolt holes. you can see into the head and there is a thin brown coating like dried water. (2nd pic). this looks like a water jacket. shouldn't there be a plug in the hole or a plate over it? i don't have any regular BP heads to compare with and nothing seems to show up in shop manuals or parts lists. surely this isn't normal? or is it?

[Flyin4stroke]

Yes there is supposed to be a freeze plug in that whole. Unless it's from a miata. Miata uses that hole to go to radiator.

[F3BZ]

thanks much. not miata. supposed to be from a familia (323) GTR. very weird. i'll have to make sure the head is checked for warpage but i don't see any evidence of severe overheating. it's hard to imagine the plug being able to fall out from behind the cover backplate.