during my hcr build, the mech made a camshaft shim drop into the spark plug hole after he torqued the head w/vet hg. he popped the head up and took out the shim and retorqued... didnt tell me. upon start up, driving around during break in, noticed overheating... checked everything we could and could not figure out why the car was pushing out water through the coolant bottle.
a few days later he conveniently remembered, we pulled it down, changed the hg and the problem went away.... until the motor blew at the race track.
who knows what caused the overheating... all I know, that HG would not have been reused if I had a say in it.