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NGK - Iridium IX Spark Plug - 6509
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NGK - Iridium IX Spark Plug - 6509

NGK
NGK6509
In stock
Iridium Spark Plug
$17.99 $11.99
Description:The NGK Iridium IX 6509 Spark Plug is designed for performance-focused applications where consistent ignition and...
$11.99
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NGK - Iridium IX Spark Plug - 6509
Description

Description:
The NGK Iridium IX 6509 Spark Plug is designed for performance-focused applications where consistent ignition and durability are important. It uses a fine-wire iridium center electrode (0.6 mm) to support a stable spark under demanding conditions, while iridium’s high melting point helps maintain electrode integrity over time in high-tech, high-performance engines.

This plug features trivalent metal plating for anti-corrosion and anti-seizing properties, corrugated ribs to help prevent flashover, and a pure alumina silicate ceramic insulator for strength and heat transfer. A copper core aids heat removal, and triple seals help prevent leakage for consistent operation. The 6509 is a resistor-type plug (5k ohm) with NGK heat range 6, a tapered seat, and a factory 0.043" (1.1 mm) gap.

Features:

  • Iridium IX fine-wire center electrode for stable spark and durability

  • Center electrode material: Iridium

  • Center electrode type: Fine wire (0.6 mm)

  • Center electrode projection: Projected

  • Ground electrode material: Nickel

  • Ground electrode shape: Taper cut (standard type)

  • Trivalent metal plating helps resist corrosion and seizing

  • Corrugated ribs help prevent flashover

  • Pure alumina silicate ceramic insulator for strength and heat transfer

  • Copper core aids heat removal

  • Triple seals help prevent leakage

  • Resistor: Yes (5k ohm)

  • Heat range: 6

  • Warranty: 60 days

  • Longevity: 50k miles

Specifications:

  • Thread diameter: 14 mm

  • Thread pitch: 1.25 mm

  • Seat type: Tapered

  • Reach: 25 mm (1")

  • Hex size: 5/8" (16 mm)

  • Terminal type: Solid

  • Gap: 0.043" (1.1 mm)

  • Torque specs: Cast iron 10.8–18 lb-ft; aluminum 7.2–14.5 lb-ft

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You must report any missing or damaged items within 14 days of delivery.
After this time, we cannot be held responsible for lost or damaged items.

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Return Window
You have 30 days from the date of delivery to request a return.
After 30 days, we are unable to accept returns, exchanges, or refund requests.

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Items must be returned in their original condition—unused, unwashed, and with all tags and packaging intact.
Certain products may not be eligible for return (e.g., special-order items, customized products, or perishable goods).
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Contact our Customer Support team to request a Return Authorization (RMA) before sending items back.
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Customers are responsible for return shipping costs unless the item was defective or incorrect.

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Please allow 5–10 business days for the refund to appear on your account.
In some cases, a restocking fee may apply (if applicable, this will be disclosed during your return authorization).

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