Originally Posted by
Raleighcopter
Loctite 2620?
High dollar stuff, rated 650°F. I've seen JB cold weld (450°f max) used on glow engine exhaust with satisfactory results but the temps with gas are higher.
New question,
what temp is estimated at the plug threads? I have no clue, I just know that much of the heat (972°f-1472°f) at the plug tip is removed/sinked away by the surrounding material.