APR - aprZ1003100 - EA888.3/4, EA855.2 and EA824 Iridium Pro Spark Plug, Heat Range 9

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. 14X26.5X16MM - Heat Range 9 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 9 spark plug (Similar: Bosch 3, Brisk 10, Denso 27, and NGK 9)
• 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
• Stronger than copper and platinum
• Perfect for upgraded APR vehicles
• Lower required supplied voltage
• Non-projected insulator design
• Thread diameter: 14mm
• Install Torque: 25 Nm
• Thread reach: 26.5mm
• Seat Type: Gasket
• Made in the EU
• Hexagon: 16mm

Refresh the ignition system with the APR Iridium Pro Spark Plug, designed for high-performance and tuned vehicle applications. Its optimized electrode design supports hard-to-ignite fuels such as ethanol, while the cooler operating temperature and improved resistance to preignition help support reliable performance under heat and load.

This heat range 9 spark plug features a non-projected insulator, gasket seat and 14 mm thread diameter with a 26.5 mm thread reach. It is designed as an excellent match for APR ignition coils and is suitable for upgraded APR vehicles. Always verify plug size, gap and heat range before installation; using the wrong-length plug can cause engine damage.

Key Features & Performance Benefits

• Iridium Construction: Provides a melting point stated as 152% higher than silver, 125% higher than copper and 38% higher than platinum.
• Heat Range 9: Intended for high-performance and tuned vehicle applications, with cooler operation than stock plugs.
• Optimized Electrode Design: Supports ignition of hard-to-ignite fuels, including ethanol.
• Ignition System Match: Designed as an excellent match for APR ignition coils, with lower required supplied voltage.

Key Product Specifications & Technical Data

• Brand: APR
• Part Number: aprZ1003100
• Heat Range: 9
• Thread Diameter: 14 mm
• Thread Reach: 26.5 mm
• Hexagon: 16 mm
• Seat Type: Gasket
• Install Torque: 25 Nm

What's Included in the Box

• One APR Iridium Pro Spark Plug

Fitment

Listed for EA888.3, EA888.4, EA855.2 and EA824 applications. Confirm application-specific fitment, plug length, gap and heat range before installation.

Air Freight Prohibited: false
Not Carb Approved: false
Carb Acknowledgement Required: false
Ltl Freight Required: false
Prop 65: Y
Part Type: automotive
Epa: N/A
Regular Stock: t
Units Per Sku: 1