# SILFR6A NGK Iridium Spark Plug | Genuine NGK Spark Plug

## 🔧 Product Description

**NGK Iridium Spark Plug – Part Number: SILFR6A**

NGK iridium spark plugs feature an iridium alloy on the centre electrode, welded on with a laser – one of the world's hardest metals, with a melting point of 2450°C, giving very high resistance to spark erosion and, on average, double the service life of a standard nickel spark plug.

## ⚙️ Key Features

-   Fine iridium-tipped centre electrode and platinum-tipped ground electrode for a slow wear rate, stable idle, improved fuel efficiency and lower emissions
-   Longer service life
-   Trivalent metal plating provides superior anti-corrosion and anti-seizing properties
-   Corrugated ribs reduce the risk of flashover
-   Pure alumina silicate ceramic insulator, providing superior strength and better heat transfer
-   Triple seals prevent leakage
-   Copper core aids in heat removal

## 📏 Specifications

-   NGK stock number: 7913
-   Thread: 14 mm
-   Reach: 26.5 mm (1.04 in)
-   Hex: 16 mm (5/8 in)
-   Seat: Gasket
-   Terminal: Solid
-   Type: Projected

## 🚘 Application

Listed in NGK's application charts for automotive vehicles.

-   Dodge Challenger (2017-2015) – 4-16 per engine
-   Dodge Charger (2017-2015) – 4-16 per engine
-   Subaru Forester (2013-2009) – 4-16 per engine
-   Subaru Impreza (2014-2008) – 4-16 per engine
-   Subaru Legacy (2009-2005) – 4-16 per engine
-   Subaru Outback (2009-2005) – 4-16 per engine
-   Subaru Tribeca (2009-2008) – 4-16 per engine
-   Subaru WRX (2014-2013) – 4-16 per engine
-   Subaru WRX STI (2018-2013) – 4-16 per engine

## 🔄 Supersession & Cross Reference

NGK's cross-reference tables list this plug against these part numbers.

-   DENSO: 4506, 4704, IKH20TT, PKH20TT

## 📦 Condition

-   Brand new genuine product
-   Supplied in original packaging

## Details

- **Price:** 53.0 AUD
- **Vendor:** NGK
- **Type:** Ignition & Controls

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 53.00 AUD | In stock |

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/silfr6a-ngk-iridium-spark-plug-genuine-ngk-spark-plug)
> Updated: 2026-09-03