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Product Information

Product Details
Part No. 4055
Warranty Details (60 DAY REPLACEMENT IF DEFECTIVE)
NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX plugs offer extreme ignitability and exceptional anti-fouling. Tapered cut ground electrode provides improved starting, idling and throttle response. The Iridium fine wire center electrode's durability is six times harder than platinum. Iridium alloy's extremely high melting point is perfect for today's engines. For even greater performance consider upgrading to an NGK Ruthenium HX plug.

Product Features:
  • SINGLE IRIDIUM TIP: Fine wire 0.6 millimeter iridium tip center electrode ensures high durability and a consistently stable spark
  • IRIDIUM ALLOY CENTER ELECTRODE: Iridium's density (6x that of platinum) and extremely high melting point is perfect for modern high efficiency engines
  • TAPERED CUT GROUND ELECTRODE: Reduced quenching design produces outstanding ignitability, improved acceleration, fuel efficiency and durability
  • SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
  • TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
  • RECOMMENDED USAGE: Modified or high performance applications, or as an upgrade to OE nickel alloy spark plugs
  • Outstanding Acceleration and High Fuel Efficiency: NGK Iridium IX spark plugs are engineered to deliver superior acceleration and enhance fuel efficiency, making them ideal for performance enthusiasts.
  • Extreme Ignitability and Anti-Fouling: These spark plugs offer exceptional ignitability and are designed to resist fouling, ensuring reliable performance in various driving conditions.
  • Improved Starting, Idling, and Throttle Response: The tapered cut ground electrode design enhances starting, idling, and throttle response, contributing to a smoother driving experience.
Specifications
Center Electrode Core Material:
Copper

Center Electrode Design:
Fine Wire

Center Electrode Insulator Tip Projection:
0.14 in

Center Electrode Projection:
Mid Projection

Center Electrode Tip Material:
Iridium

Electrical Terminal Type:
Removable Nut

Electrode Core Material:
Iridium

Electrode Tip Material:
Iridium

Gap Size:
0.032 in

Grade Type:
Performance

Ground Configuration:
J-Gap

Ground Electrode Core Material:
Nickel

Ground Electrode Quantity:
1

Ground Electrode Tip Design:
Taper Cut

Ground Electrode Tip Material:
Nickel

Ground Strap Quantity:
1

Hex Size:
13/16"

Insulator Height:
2.20 in

Insulator Material:
Ceramic

Manufacturer Heat Range:
7

Pre-Gap Size:
.032 in

Reach:
0.750 in

Resistance:
5000.0 ohm

Resistor:
Yes

Resistor Type:
Yes

Seat Type:
Flat

Shorty Spark Plug:
No

Skirt:
No

Skirt Length:
0.0 in

Thread Diameter:
0.551 in

Thread Size:
M14 - 1.25

Tip Configuration:
Loose

Washer Type:
Crush

Washer(s) Included:
Yes

Wrench Diameter:
13/16 in
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