Because the OP didn't say what he had for a 360 and what has been done to it I looked up a 1980 360 out of a pick up to find the 14 Champions. Have to start somewhere. I didn't look up whether the 80 had a egr or not. At least I looked it up and didn't just pull a number off the top of my head. "I use a *** in mine but it has more compression or a such and such ignition or headers or the like" doesn't work here. We really don't have a clue what the op has for a 360. The stock plug is the place to start. Pardon me while I look up other 360's to see where the heat ranges go between the years.
