Iridium IX Spark Plug
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Iridium IX Spark Plug Iridium IX Spark Plug
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NGK Iridium IX Spark Plug

Part No. 3689 Warranty Details  

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Laser-welded iridium center electrode is resistant to heat, corrosion and electrical wear. The tapered ground electrode minimizes quenching. Provides outstanding acceleration, high fuel efficiency and durability.

Product Features:
  • 0.6 mm iridium-tip center electrode provides durability and a high melting point
  • Taper-cut ground electrode shape provides improved flame reproduction
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Center Electrode Core Material:Copper Core
Center Electrode Tip Material:Iridium
Electrode Core Material:Iridium
Electrode Tip Material:Iridium
Gap Size:0.040 in
Ground Configuration:Standard
Ground Electrode Core Material:Nickel Core
Ground Electrode Quantity:1
Ground Electrode Tip Design:Taper Cut
Ground Strap Quantity:1
Hex Size:5/8
Manufacturer Heat Range:6
Reach:17.5 mm
Resistor:Yes
Seat Type:Tapered
Shorty Spark Plug:No
Thread Diameter:14 mm
Tip Configuration:Solid
Type:Iridium IX
Wrench Diameter:5/8 in

REVIEW SNAPSHOT®

by PowerReviews
NGKIridium IX Spark Plug
 
3.7

(based on 3 reviews)

Ratings Distribution

  • 5 Stars

     

    (2)

  • 4 Stars

     

    (0)

  • 3 Stars

     

    (0)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (1)

67%

of respondents would recommend this to a friend.

Reviewed by 3 customers

Displaying reviews 1-3

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5.0

Great plug

By 

from charleston sc

Verified Reviewer

Pros

  • power idle

Cons

    Best Uses

      Comments about NGK Iridium IX Spark Plug:

      Using in my Harley 04 and just installed in 99 ranger 4x4, great improvement in both.

      • Was this a gift?:
      • No

      (1 of 1 customers found this review helpful)

       
      5.0

      Works great in SVT Lightning w/pulley

      By 

      from Dallas, NC

      About Me Auto Enthusiast, Truck Enthusiast

      Pros

      • Durable
      • Easy To Install
      • Increases Power

      Cons

        Best Uses

        • Everyday Driving
        • Great Alt Plug For Tr6
        • Performance Driving
        • Racing

        Comments about NGK Iridium IX Spark Plug:

        Great plug for forced induction applications (SVT Lightning w/pulley) needing a TR6 heat range plug. Search Lightningrodder.com for correct heat range and gap depending on boost level.

        (1 of 4 customers found this review helpful)

         
        1.0

        Hmmm...not that good

        By 

        from Richmond, VA

        Pros

        • Correct fit

        Cons

        • Decreases Gas Mileage
        • No Improvement In Performance

        Best Uses

        • Everyday Driving
        • Long distance commute

        Comments about NGK Iridium IX Spark Plug:

        Gap for my Mazda3 2.3 forces the ground head too far away from the electrode tip and creates an angle of .251 degrees to horizontal. Misfiring occurs immediately and constantly. Vehicle went from 33mpg to 25mpg. Buy the motorcraft as the ground head is long enough away to allow for larger gap setups without the presence of any angle rotation.

        • Car & Truck:
        • Auto Enthusiast, Casual Driver, Mechanic

        Displaying reviews 1-3

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