Take your tuning to the next level with the HKS MR45XLB Super Fire Racing Spark Plug. This premium Ruthenium alloy plug is the ultimate ignition upgrade for modern high-performance engines, including the Toyota GR Supra (A90/A91) and the BMW B-Series (B58/B48).

The MR45XLB features an NGK Heat Range 9 equivalent, providing the "colder" thermal performance required for high-boost, remapped, and track-driven vehicles. By dissipating heat more efficiently, these plugs significantly reduce the risk of pre-ignition and engine knock.

Why Choose the MR-Series Ruthenium?

• Ruthenium Alloy Center Electrode: Superior to Iridium, Ruthenium offers a higher melting point and better oxidation resistance, ensuring a stable spark even under the extreme pressures of modern GDI engines.

• 0.6mm Ultra-Fine Tip: Reduces the ignition voltage required, resulting in a more powerful spark, improved throttle response, and smoother idling.

• Bi-HEX 14mm Fitment: Designed specifically for the specialized M12 thread and 14mm Bi-Hex (12-point) wrench size used in the latest BMW and Toyota performance heads.

• Anti-Vibration Short Tip: The ground electrode is shortened and reinforced with a platinum alloy tip to withstand high-RPM vibrations and maximize durability.

• Copper Core Technology: Integrated copper core in the ground electrode helps pull heat away from the tip faster, keeping the plug within its optimal operating temperature.

Technical Specifications

High-Performance Vehicle Fitment

The HKS MR45XLB is the professional choice for:

• Toyota: GR Supra (A90 / A91) — 3.0L B58 & 2.0L B48

• BMW M-Performance: M240i, M340i, M440i, X3 M40i, Z4 M40i (B58 Engine)

• BMW 1/2/3/4/5 Series: F & G Chassis models with B48 (4-cyl) or B58 (6-cyl) engines.

• Mini: Cooper S & JCW (F56/F54/F60) with B46/B48 engines.

Purchasing Note: All HKS plugs are sold individually in Australia. For a 6-cylinder B58 (Supra/M340i), please order Quantity: 6. For a 4-cylinder B48 (Mini/330i), please order Quantity: 4.