[L-head]

Years ago, I had a flathead cam from an old 59A that I tore down for parts. The cam had what looked like air pockets, bubbles, pores throughout the whole cam. It was that way on the lobes and brg surfaces. I could not believe that it had run for years that way and still looked like it was still usable. Has anybody ever seen anything like that? How could that make it through "quality control"?