... in spark plug applications. Spark plug taps. Also known as Piloted Reamer Taps,pilot nose taps, for use in spark plug applications. Spark Plug Taps ... tap sectionwhich cuts the proper threads for the HeliCoil spark plug insert to be installed. No prior drilling of ... out threads is needed with HeliCoil spark plug taps. Material: carbon steel,alloy steel,high speed steel. Spark Plug Tap (Pilot nose Taps ...