Short BB Spk Plug Clear Headers, I think.

Update. Car (short plugs) have about 250 miles on it and several different extended balls to the wall romps (308 gears). No plugs falling out or disintegrating. Not a miss fire. So, my opinion is - this plug works great. Will update after the Jensen Nationals. Going to do a lot of foot in the carburetor pulls, shooting fuel and oil everywhere for several days.
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