APR EA825/EA839/9A2 Iridium Pro Spark Plug - Heat Range 10 - 12mm x 26.5mm x 14mm - SINGLE
$53.99
Refresh your ignition system in one shot with APR Iridium Pro Spark Plugs and pair with APR Ignition Coils – engineered to work together for a stronger, more consistent spark. Each is a direct-fit upgrade designed to support smoother idle, sharper throttle response, and reliable performance under heat and load—whether you’re stock or running higher boost and power upgrades.
12X26.5X14mm - Heat Range 10
Always check sizes, gap, and heat range specs before installing. Installation of the wrong length plug can cause damage to the engine. You must verify this before installing the plug.
- 152% higher melting point than silver, 125% higher than copper, and 38% higher than platinum.
- Heat range 10 spark plug (Similar: Bosch 2, Brisk 8, Denso 31, and NGK 10)
- 1 step colder older than OEM (2.9T/3.0T EA829, 2.0T/2.5T/3.0T/3.7T 9A2)
- Optimized electrode design for hard to ignite fuels, such as ethanol
- Designed for high performance / tuned vehicle applications
- Cooler operating temperature than stock plugs
- Resists preignition better than stock plugs
- An excellent match for APR ignition coils
- 2 steps colder than OEM (4.0T EA825)
- Stronger than copper and platinum
- Perfect for upgraded APR vehicles
- Lower required supplied voltage
- Non-projected insulator design
- Supplied Gap: .55mm +- .05mm
- Insulator Material: Ceramic
- Thread diameter: 12mm
- Install Torque: 17 Nm
- Thread reach: 26.5mm
- Seat Type: Gasket
- Made in the EU
- Hexagon: 14mm
Upgrade your ignition system with the APR Iridium Pro Spark Plug, part number aprZ1004081. Designed for high-performance and tuned vehicles, this heat range 10 plug provides a strong, consistent spark under demanding heat, cylinder pressure, and boost conditions. It is engineered to complement APR ignition coils and is suitable for applications ranging from stock vehicles to platforms with increased power and ethanol-based fuels. Always verify application, plug reach, heat range, electrode gap, and fitment before installation to help prevent engine damage.
The Iridium Pro construction offers a melting point substantially higher than silver, copper, and platinum, supporting durability during severe operating conditions. Its optimized electrode design requires lower supplied voltage and helps improve ignition reliability, while the non-projected insulator and cooler operating temperature provide increased resistance to preignition compared with standard plugs. The plug is one step colder than OEM on 2.9T and 3.0T EA839 engines, as well as 2.0T, 2.5T, 3.0T, and 3.7T 9A2 applications. It is two steps colder than OEM for 4.0T EA825 engines.
This APR spark plug uses a 12 mm thread diameter, 26.5 mm thread reach, gasket seat, ceramic insulator, and 14 mm hex. The supplied gap is approximately 0.022 inch, with a tolerance of approximately 0.002 inch. Install torque is 13 lb-ft, and the plug is made in the European Union. Confirm the required specifications for your vehicle before installation, since using an incorrect plug length or heat range can cause serious engine damage.
Features:
- APR part number aprZ1004081
- Heat range 10 performance spark plug
- Designed for high-performance and tuned vehicle applications
- Compatible with APR ignition coils
- One step colder than OEM for select EA839 and 9A2 engines
- Two steps colder than OEM for 4.0T EA825 engines
- Optimized electrode design for difficult-to-ignite fuels, including ethanol
- Cooler operating temperature than stock plugs
- Improved resistance to preignition compared with stock plugs
- Iridium construction with high-temperature durability
- Lower required supplied voltage
- Non-projected insulator design
- Supplied gap: approximately 0.022 inch ± 0.002 inch
- Ceramic insulator material
- 12 mm thread diameter
- 26.5 mm thread reach
- Gasket seat type
- 14 mm hex
- Install torque: 13 lb-ft
- Made in the European Union