# BPR6EIX NGK Iridium Spark Plug | Genuine NGK Spark Plug

## 🔧 Product Description

**NGK Iridium Spark Plug – Part Number: BPR6EIX**

Iridium NGK spark plugs offer a longer service life than a standard nickel-tipped spark plug: while nickel-alloy plugs offer a service life of roughly 20,000-40,000km, NGK Iridium IX spark plugs offer a service life of up to 60,000km, so fewer replacements are needed over time despite the higher initial cost.

Precious-metal spark plugs like the NGK Iridium IX also offer higher ignitability, achieved with an exposed fine-tip centre electrode that promotes superior flame growth compared with a standard spark plug. Iridium has a much higher melting point (2410°C) than nickel (1453°C), allowing the centre electrode diameter to be reduced from 2.5mm to 0.6mm – a smaller electrode mass that reduces the impedance to flame progress, helping acceleration, fuel consumption and idle quality.

## ⚙️ Key Features

-   Fine iridium-tipped centre electrode for a slow wear rate and stable idle
-   Longer service life than standard nickel plugs
-   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
-   Copper core aids in heat removal
-   Triple seals prevent leakage

## 📏 Specifications

-   NGK stock number: 6637
-   Thread: 14 mm
-   Reach: 19 mm (3/4 in)
-   Hex: 20.8 mm (13/16 in)
-   Seat: Gasket
-   Type: Projected

## 🚘 Application

Listed in NGK's application charts for marine, motorcycle, ATV and snowmobile equipment and automotive vehicles. The gap is not the same on all of them – the chart lists between 0.5 mm and 1.0 mm depending on the engine, so check the line for yours.

-   Chrysler LM318A (8 CYL) – Inboard Engine
-   Chrysler LM318AC (8 CYL) – Inboard Engine
-   Chrysler LM318B (8 CYL) – Inboard Engine
-   Chrysler LM318BC (8 CYL) – Inboard Engine
-   Chrysler LM318BJ (8 CYL) – Inboard Engine
-   Chrysler LM318BT (8 CYL) – Inboard Engine
-   Chrysler LM318BV (8 CYL) – Inboard Engine
-   Chrysler LM318D (8 CYL) – Inboard Engine
-   Chrysler LM340B (8 CYL) – Inboard Engine
-   Chrysler LM340BJ (8 CYL) – Inboard Engine
-   Chrysler LM340BT (8 CYL) – Inboard Engine
-   Chrysler LM340BV (8 CYL) – Inboard Engine
-   Chrysler M91D (4 CYL) – Inboard Engine
-   Chrysler M91F (4 CYL) – Inboard Engine
-   Chrysler M273A (8 CYL) – Inboard Engine
-   Chrysler M273B (8 CYL) – Inboard Engine
-   Chrysler M273BT (8 CYL) – Inboard Engine
-   Chrysler M360A (8 CYL) – Inboard Engine
-   Chrysler M360B (8 CYL) – Inboard Engine
-   Chrysler M360BC (8 CYL) – Inboard Engine
-   Chrysler M360BJ (8 CYL) – Inboard Engine
-   Chrysler M360BT (8 CYL) – Inboard Engine
-   Chrysler M360BV (8 CYL) – Inboard Engine
-   Mercruiser 8.2 HO DTS ECT (8 CYL GM BIG BLOCK) – Inboard Engine
-   Mercruiser 8.2 HORIZON DTS ECT (8 CYL GM BIG BLOCK) – Inboard Engine

That is the 25 most common of 377 applications NGK's charts list for this plug – ask us to check yours.

## 🔄 Supersession & Cross Reference

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

-   Bosch: 4216, 4225, 4310, 4477, 4506, 4510, W6DP, W6DP0 and 9 more
-   DENSO: 3045, 3065, 3116, 3291, 4709, 5306, 5502, IW20 and 8 more
-   Champion: 247, 248, N10PY, N8GY, RN10GY, RN79PYP17, RN79PYP25, RN9GY
-   Autolite: XP63, XP63DP2, XP64, XP64DP2, XS63, XS63DP
-   Torch: 8012, F6RTI, F6RTP
-   Beck Arnley: 1765184

## 📦 Condition

-   Brand new genuine product
-   Supplied in original packaging

## Details

- **Price:** 42.0 AUD
- **Vendor:** NGK
- **Type:** Ignition & Controls

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 42.00 AUD | In stock |

## Images

- BPR6EIX NGK iridium spark plug
- BPR6EIX NGK iridium spark plug firing end

---

> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/bpr6eix-ngk-iridium-spark-plug-genuine-ngk-spark-plug)
> Updated: 2026-09-03