The studs came pre-installed on the AFR 185 heads. I don't think it was a stud problem as much as it was operator error. The nut on that stud had backed off almost 1/4". I think the rocker just got caught rocking back and forth and snapped the stud. It made a loud pop for sure.
These heads are known as some of the best for racing so not too worried about the studs. Just worry about me getting them tight when they are adjusted. These lifters have always made quite a bit of noise and I have checked them twice before. Just left one a little loose I think. More to come I am sure. Larry