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    Autolite High Performance Racing Resistor Spark Plug

    Part # AR25
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    Save $3 per Spark Plug by mail when you buy 4 or more ACDelco Professional Iridium Spark Plugs. See rebates page for details.
    • Product Details

      Part No. AR25

      Warranty Details (2 YR REPLACEMENT IF DEFECTIVE)

      The ground electrode is cut-back from the center electrode to provide a gap. The face of the ground electrode is concave to provide a constant gap to the center electrode. This plug is designed use in all aftermarket cylinder heads used in different types of racing venues including oval and road racing.

      Product Features:

      • Opens spark face for better ignitability of flame kernel
      • Retains less heat, transfers heat to shell faster - reduces risk of pre-ignition
      • Dyno testing has shown proven power gains
      • Cut-back ground electrode evolved from practice of grinding back the side electrode

    • Specifications
      • Electrode Tip Material:Resistor
        Reach:.460 in
        Seat Type:Tapered
        Thread Diameter:14 mm
        Tip Configuration:Power
        Wrench Diameter:5/8 in
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