93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
Probably a fried exhaust valve, blown head gaskets don't generally read that low unless something is wrong with the tester.
Very, at that price I'd have them do all the guides, then you get another 170-200k out of the engine and the bottom end finishes wearing out the same time as the head next time.I called a local machine shop here in Houston and they quoted me 220 to do the milling and the other tests on the head. They said it would be $10 to replace the broken valve and another $10 if the guide needed replaced. Does that sound reasonable?