Colder plugs?

Seafoam on occaision and VP Madditive. Maybe a can every 1000 miles or so
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So why the sea foam and why the additive? Do you not need the additive for every tank?

I don't think you are off on heat range. But the timing looks high. If the timing is correct, then the plug is too hot. Like I said, I'd rather read heat off the shell. That black shell makes it hard. Almost impossible with a picture.