Thank you H8PVMNT!
I agree with H8PVMNT.... excellent commentary!
I've tried most all of the various brands over the years, including iridiums. The plats and iridiums typically have a longer life. I tend to install what the factory specs. If you are tuning, then installing the basic copper plug is a good idea and plug readings are important. I think changing spark plugs once a year (15K to 20K miles) along with the cap & rotor is a cheap investment for keeping your engine running in good tune. I also prefer a quality set of wire core spark plug wires.
Although there's lots of debate and opinions on spark plugs, I don't recall being able to notice a difference in one brand to the other.
Regarding temp ranges, I would make those changes carefully.
Good ol' copper spark plugs work fine.
Gnarls.
