ORIGINAL: buzzard bait
All the usual sources refer to matching plug heat to nitro content. But it seems like this info should also help when you have an engine designed for no nitro, but all your fuel is 10%. Usual advice is to add a head shim. But you can just use a cool plug, right? Jim
Maybe
It depends ome engines with a cooler plug may let you do that other engines will continue to predetonate.