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NGK SPARK PLUG SILMAR8A9S 90992 31909-MJP-G51 HONDA

£25.57

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UK delivery £4.99, free over £60 2–4 business days

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The NGK SILMAR8A9S Spark Plug is a Laser Iridium plug engineered for high ignitability, longevity, and stable combustion. Designed with fine wire iridium and platinum elements, it offers superior resistance to wear and fouling, and supports efficient engine performance. Features include a fine wire iridium center electrode and fine wire platinum ground electrode for slow wear rate and stable combustion, trivalent metal plating for enhanced anti-corrosion and anti-seizing, corrugated ribs to prevent flashover, a pure alumina silicate ceramic insulator for strength and heat transfer, a copper core for heat removal, and triple seals to prevent leakage. Specifications include a 10mm shell thread diameter, 1.0mm thread pitch, gasket seat type, 26.5mm reach, 9/16 inch (14mm) hex size, solid terminal type, and a 0.035 inch (0.9mm) gap. The center electrode is 0.6mm, fine wire, and non-projected. Cross-reference OEM part number: 31909-MJP-G51.

Specifications
SKU
37-SILMAR8A9S
Brand
NGK
Availability
In Stock (9)
SKU
37-SILMAR8A9S
Brand
NGK
Availability
In Stock (9)
Delivery2–4 business days
14-Day ReturnsHassle-free
Easy CheckoutCard friendly
Product details

FULL DESCRIPTION

NGK SPARK PLUG SILMAR8A9S

The NGK SILMAR8A9S Spark Plug is a Laser Iridium plug engineered for high ignitability, longevity, and stable combustion. Designed with fine wire iridium and platinum elements, it offers superior resistance to wear and fouling, and supports efficient engine performance.

Key Features:

  • Fine wire iridium center electrode and fine wire platinum ground electrode for slow wear rate and stable combustion
  • Trivalent metal plating for enhanced anti-corrosion and anti-seizing
  • Corrugated ribs prevent flashover
  • Pure alumina silicate ceramic insulator for strength and heat transfer
  • Copper core aids in heat removal
  • Triple seals prevent leakage

Specifications:

  • Shell thread diameter: 10mm
  • Thread pitch: 1.0mm
  • Seat type: Gasket
  • Reach: 26.5mm
  • Hex size: 14mm
  • Terminal type: Solid
  • Gap: 0.9mm
  • Center electrode material: Iridium
  • Center electrode type: Fine wire
  • Center electrode size: 0.6mm
  • Center electrode projection: Non-projected

Cross-Reference OEM Part Number: 31909-MJP-G51

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UK delivery is £4.99, or free on orders over £60. Orders ship within 3 working days, then delivery takes 2–4 business days. Delivery details

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