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$22.00 NZD inc. GST

Priced / Sold Individualy.
Select your Quantity below. (preferably in lots of 4 or 8)

NGK Iridium Spark plug

Gap: .04″ (1mm)

If ordering 8 plugs or more use the coupon code ‘v8’ to take $1 per plug off the price

In stock

SKU: NGK-3689 Category:


NGK’s IX Iridium Series Plugs were Designed Specifically for the Performance Enthusiast.


-Fine Wire Center Electrode Ensures High Durability and a Consistently Stable Spark
-Iridium Alloy has an Extremely High Melting Point, Perfect for Today’s High-Tech, High Performance Engines
-Trivalent Metal Plating Provides Superior Anti-Corrosion and Anti-Seizing Properties
-Corrugated Ribs Prevent Flashover
-Pure Alumina Silicate Ceramic Insulator, Provides Superior Strength and Better Heat Transfer
-Copper Core Aids in Heat Removal

Suitable for holden SS LS1, and other LS engines.
Similar to factory replacement plug however this plug has a slightly smaller gap. (.04″ vs stock .06″)

and is 1 step colder than stock.
this plug would more suit high output NA engine or a boosted engine.

is also an aftermarket replacement for the Mustang 5.8 Supercharged engine.

Center Electrode Core Material Copper Core
Center Electrode Tip Material Iridium
Gap Size 0.04 in (1mm)
Ground Electrode Quantity 1
Hex Size 5/8″
Insulator Height ISO
Manufacturer Heat Range 6
Additional Info 5K Ohm
Seat Type Tapered
Reach 17.5mm
Thread Diameter 14 MM
Ground Electrode Tip Design Taper Cut
Ground Configuration Standard
Ground Electrode Core Material Nickel Core

Additional information

Weight 1 kg

Holden, Chevrolet, SS, SV8, LS1, LS, Mustang 5.8 Supercharged, LS series V8 engines

Alternate Part numbers


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