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Denso Iridium Power Performance Spark Plug, 03-06 350Z

Denso Iridium Power Performance Spark Plug, 03-06 350Z
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Part #:12-3112
Price: $12.95
Description:
Denso Iridium: By harnessing the power of Iridium, Denso was able to shrink the surface area of the center electrode - the critical component of a spark plug. Unlike a typical platinum plug that has a 1.1mm diameter center electrode, these DENSO Iridium plug electrodes for your 350Z have an ultra-fine 0.7mm diameter. This means that the voltage requirements are decreased while firing performance is greatly improved. Iridium alloy is superior to platinum based on hardness, strength and melting point. These plugs can handle temperatures in excess of 4000°F. Denso Iridium alloy plugs are composed primarily of Iridium, but mix in rhodium for oxidation wear. Pure Iridium has a melting point of almost 700°C higher than platinum, and had the greatest potential for resistances against wear. Iridium by itself is susceptible to oxidation wear at temperatures over 900°C. Further testing proved that Iridium alone would not meet Denso's demanding standards. After testing other pure metals combined with Iridium, rhodium proved to be the best choice to meet the needs of Denso's spark plug engineers. Sold individually, 6 required per car.

U-Groove: Denso's patented U-Groove design (patented in 1972) changed the industry standard in the mid 1970s by providing a better design that virtually eliminates erratic starts caused by poor fuel mixture. The U-Groove results in less flame dissipation making the spread of the flame nucleus easier and therefore yielding greater firing energy. It gives the flame a groove to grow in, thereby creating a larger flame front for a complete combustion. On a conventional plug, the flat electrode design crushes the spark, and the overall volume of the flash front is smaller. The conventional method to improve firing was to increase the spark gap. This has a negative effect on the spark. With a U-Groove firing can be greatly improved without increasing the spark gap.

Tapered Cut: To help improve ignitability Denso's tapered cut ground electrodes minimize the portion that comes in contact with the flame nucleus. Because the area of the ground electrode where the tapered cut comes into contact with the flame nucleus is small, the heat lost to the electrode is lessened and firing performance improves dramatically. The surface area and weight of the ground electrode tip is reduced along with the load in terms of heat and vibrations. This means the spark plug can cope with heavier driving conditions.

Laser Welding: Denso's Iridium Alloy had all of the qualities to produce the world's best spark plug, but conventional tooling prevented DENSO from mass manufacturing. Due to the high melting point there wasn't a welding process hot enough to join the Iridium tip to the nickel base. Necessity to melt the Iridium to the nickel base forced DENSO to pioneer its third patent, the 360° Laser Welding Process, to provide a seal so reliable; the electrode resists wear even in the worst combustion conditions.

Model Guide:
Nissan 350Z

Code Guide:
Nissan Z33

Year Guide:
2003, 2004, 2005, 2006



1. Iridium Plug Insulator: The insulators are made of a highly purified alumina powder, which gives exceptional dielectric strength and thermal conductivity at high temperatures, as well as greater physical strength.


2. Five-Rib Design: (use dia01 image)The five-rib design prevents flashover and decreases voltage loss.


3. Copper-Glass Seal: A special mixture of copper and glass powder bonds the center electrode and insulator together for a gas tight seal. Proper heat is maintained and hot combustion gases are excluded.


4. Copper-Cored Center Electrode: A special center electrode incorporates copper into the core of the nickel chrome binary alloy. This gives superior thermal conductivity and increases the operating range.


5. U-Groove Ground Electrode: The originally patented U-Groove allows the spark to fill the gap formed by the U. This ball of fire develops a larger and hotter flash front so combustion is complete.


6. Patented Iridium Center Electrode: Utilizes Iridium to create the world's smallest center electrode tip for maximum firing performance and reduced voltage requirements.


7. Tapered Cut: Improves firing performance by reducing quenching.


8. 360° Laser Welding: DENSO perfected the Laser Welding Process, which provides a 360° seal so reliable the electrode resists wear even in the harshest conditions.


9. 100% Pre-Fired: All DENSO spark plugs are pre-fired at the factory to assure highest possible quality.

Some parts may not fit every version of every year listed. See product Title & Description for any application breakdowns or customization options, and contact us with any questions.

  • 2003 Nissan 350Z
  • 2004 Nissan 350Z
  • 2005 Nissan 350Z
  • 2006 Nissan 350Z
Attention California Customers:
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov.
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