Ignite your engine's true potential with the HKS M40XL Super Fire Racing Spark Plug. This premium XL Type plug is the definitive performance upgrade for high-output turbocharged engines, including the Mitsubishi Evolution X and the Hyundai N-Performance range.
Rated at an NGK Heat Range 8 equivalent, the M40XL is a "colder" plug designed to dissipate heat faster, preventing pre-ignition and engine knock in vehicles running increased boost or aftermarket tuning.
0.6mm Iridium Alloy Center Electrode: Minimizes voltage requirements to produce a hot, concentrated spark, improving throttle response and combustion stability.
Platinum Ground Electrode: Features a square platinum chip for superior durability, ensuring your spark gap remains consistent even under extreme racing conditions.
Anti-Vibration Short Tip: The outer electrode is shortened and tapered to reduce weight and resist the high-frequency vibrations found in high-RPM engines.
Thermal Edge Technology: A specialized ceramic insulator design helps discharge carbon deposits during idling, virtually eliminating the risk of fouling.
Superior ISO/XL Fitment: Specifically designed for modern "Long Reach" cylinder heads that require a 16mm hex wrench.
HKS SKU: 50003-M40XL
Plug Type: XL Type (Long Reach)
Heat Range: NGK #8 Equivalent
Thread Size: $12\text{mm} \times 26.5\text{mm}$
Wrench Size: $16\text{mm}$
Electrode: Iridium Center / Platinum Ground
The HKS M40XL is the go-to performance choice for:
Mitsubishi: Lancer Evolution X (CZ4A - 4B11T)
Hyundai: i30N, Veloster N, Kona N (2.0L Turbo), i30 SR/N-Line (1.6L Turbo)
Kia: Stinger (2.0L/3.3L TT), Cerato GT, Proceed GT
Mercedes-Benz: Select AMG 5.5L Bi-Turbo engines
Pro Tip: Spark plugs are sold individually in Australia. For a Mitsubishi Evo X or Hyundai i30N, please order Quantity: 4. For a Kia Stinger V6, please order Quantity: 6.
$795.00
$795.00
$760.00
$1,999.00
$6,995.00
$40.00
$132.00