rgnprof wrote:
Bolts were already broken - really loud until it warmed up some. In my experience, every single bolt/stud has been broken off pretty flush to the head...
I suspected they had sheared at the head. That was always the case with the Pontiac Fiero 2.8L-V6 engines I worked on. I spent many hours as a contortionist getting sheared studs out of those engines. Those manifolds were piped but they were not headers. I think they failed because the pipes would warp from the heat causing undue stress on the bolts. I wonder if a cast manifold would have been less trouble.
