Carbon tracking through rotor. More HEI woes.

Here are some that show up to .080. I cannot remember what year or which model used .120, but there were a few. I could spend all night lookin but I have more important things to do. You get the idea.

https://www.oreillyauto.com/shop/b/.../b14eb31b13d7/1976/oldsmobile/98?q=spark+plug