[Half-Inch Stud]

I'm reminder of my stepson's Auto Technician Training manuel; it had many images of valve head and seat failures. As i read the caption for each failure mode ( and brand engine) I assessed the conclusion "well that never happens to a PONTIAC HEAD.

I sure got to wondering how PMD was so fortunate, and figured on the rewards from good R&D.

As we all know, the PMD heads #1 stock wearout/failure mode is worn valveguides, leading to oil consumption.