Description
The Dinan D640-0003 Iridium Spark Plug is a performance-oriented replacement spark plug designed for BMW B48 TU and B58 TU1 engines, including Gen 2 B48 and Gen 3 B58 applications.
Designed for both tuned and stock engines, the D640-0003 uses an iridium center electrode with a copper core to provide a strong, consistent spark while operating at a cooler temperature than the factory plug. Its colder Heat Range 12 specification, similar to NGK 8, makes it particularly well suited to applications experiencing increased boost, cylinder pressure, cylinder temperatures, or overall engine output.
The iridium electrode is highly resistant to heat and wear, while the copper core helps dissipate heat efficiently. Dinan also designed the electrode configuration to reduce the voltage required to produce a strong spark and improve ignition performance with difficult-to-ignite fuels such as ethanol.
The D640-0003 can also be paired with Dinan ignition coils, where applicable, for a complete ignition-system upgrade.
Fitment
BMW B48 TU – Gen 2 B48
BMW B58 TU1 – Gen 3 B58
Engine Applications:
- B48 TU / Gen 2 B48
- B58 TU1 / Gen 3 B58
Spark Plug Part Number: D640-0003
Compatible OEM Part Number: 12125A523E0
Heat Range: 12, similar to NGK 8
Always verify the engine generation, spark plug dimensions, heat range, gap, and OEM part number before installation.
What's Included
- 1 × Dinan D640-0003 Iridium Spark Plug
Sold individually.
Key Features
- Iridium Center Electrode: High-strength iridium electrode provides excellent heat resistance and durability.
- Copper Core: Copper center electrode core helps dissipate heat efficiently.
- Heat Range 12: Colder heat range comparable to NGK 8.
- High-Performance Application: Designed for high boost, high cylinder pressure, high cylinder temperatures, and high-power applications.
- Tuned & Stock Compatibility: Suitable for both tuned and stock engines where the D640-0003 application is appropriate.
- Cooler Operating Temperature: Designed to operate cooler than the stock plug.
- Improved Ignition: Requires less supplied voltage to produce a strong spark.
- Ethanol Compatible Design: Electrode design is optimized for hard-to-ignite fuels such as ethanol.
- Preignition Resistance: Designed to resist preignition better than standard plugs.
- Projected Insulator: Projected insulator design supports the plug's ignition characteristics.
- Performance Grade: Developed as a performance-oriented ignition component.
- Dinan Compatibility: Pairs well with Dinan ignition coils where applicable.
- Made in the EU: Manufactured in the European Union.
Specifications
- Brand: Dinan
- Part Number: D640-0003
- Product Type: Iridium Spark Plug
- Category: Ignition
- Subcategory: Secondary Ignition
- Grade: Performance
- Center Electrode Tip: Iridium
- Center Electrode Core: Copper
- Center Electrode Projection: Short Projection
- Heat Range: 12
- NGK Equivalent Heat Range: Similar to NGK 8
- Thread Diameter: 12 mm
- Thread Reach: 26.5 mm
- Hex Size: 14 mm
- Hex Type: Bi-Hex
- Terminal Type: Cup
- Seat Type: Flat
- Insulator Material: Ceramic
- Supplied Gap: 0.5 mm
- Install Torque: 15 + 25 Nm
- Indexed: No
- Emission Code: 7
- Warranty: 1 Year / Unlimited Miles
- UPC: 810215392988
- Manufacturing: Made in the EU
- OEM Cross Reference: 12125A523E0
Iridium & Copper Electrode Technology
The Dinan D640-0003 combines an iridium electrode tip with a copper core to provide a durable and heat-resistant ignition solution.
According to Dinan, iridium has a significantly higher melting point than silver, copper, and platinum. The electrode is also designed to resist melting and cracking while providing efficient heat dissipation.
The plug's design helps produce a strong spark with lower required voltage, making it well suited to demanding ignition environments.
High-Boost & Performance Applications
The D640-0003 is designed for engines operating under increased boost, cylinder pressure, cylinder temperature, and power output.
Its colder heat range and heat-resistant iridium construction make it a suitable option for applicable tuned engines while also allowing use on compatible stock applications.
Dinan also optimized the electrode design for difficult-to-ignite fuels such as ethanol, providing additional flexibility for performance-oriented engine setups.
Installation & Important Fitment Notice
Always verify the spark plug dimensions, heat range, electrode gap, and engine application before installation.
The D640-0003 has a 12 mm thread diameter, 26.5 mm thread reach, flat seat, and 0.5 mm supplied gap. Installing a spark plug with the incorrect length or specification can cause engine damage.
The specified installation torque is 15 + 25 Nm. Always follow the applicable vehicle manufacturer's service procedure and verify the correct torque specification for your specific application before installation.
Emissions & Legal Information
The Dinan D640-0003 carries Emission Code 7. Dinan states that the product is supported under the applicable provisions of the EPA Tampering Policy dated November 23, 2020, based on testing intended to establish emissions compliance.
Important: This product is not legal for sale or use in California according to the current manufacturer listing. California Air Resources Board testing for 50-state compliance is pending.
The standard shipping rate applies to orders within the continental United States. If you intend to place an order outside of the continental US, please reach out to support@x-ph.com for assistance.
