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HKS M40HL Super Fire Racing Spark Plug

by HKS
SKU 50003-M40HL
Original price $26.97 - Original price $26.97
Original price
$26.97
$26.97 - $26.97
Current price $26.97

Here, you are looking at the HKS M50HL Super Fire Racing Spark Plug for the 2015-2021 WRX.

Features:

  • 0.6mm Iridium Alloy Center Electrode - Iridium alloy center electrode reduces voltage requirement and improves ignition performance and durability.
  • Outer Electrode with Platinum Chip - The outer electrode incorporates a square platinum chip which improves durability, and combining with the iridium center electrode boosts ignition performance.
  • The outer electrode features a shortened tip design and tapered shape while maintaining the necessary space for proper ignition.
  • Short Type Outer Electrode (Anti-Vibration) - The outer electrode has been shortened and engineered with the ideal shape to decrease weight for resistance against vibration. This anti-vibration design improves longevity of the outer electrode.
  • Thermal Edge - After long idling or under various combustion conditions, carbon buildup can occur causing misfires. The thermal edge of the ceramic insulator discharges to help decrease carbon deposits.
  • Spark Support Gap - Discharge occurs in the spark support gap (space between the tip of insulator and the base of the outer electrode) to help prevent carbon buildup.

Performance and Efficiency

  • Increased Ignition Performance - Decreased voltage requirement strengthens ignition performance under harsh conditions like lean mixture or high boost pressure.
  • Improved Durability - New material and design improve durability which allows for use under hard combustion conditions like continuous high load during circuit driving or aggressive tuning. Improper combustion conditions and wrong heat range selection may cause damage to the spark plug.
  • Decreased Carbon Deposits - Thermal edge and spark support gap help prevent carbon buildup for better ignition under various combustion conditions.

Sold Individually

    Customer Reviews

    Based on 1 review
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    S
    Sean Kincade
    2017 WRX

    These worked great for me with running a custom tune. If you’re running stock, maybe stick with NGK. Good spark plugs from a good name brand though, I’d recommend them.

    Sean,

    Thank you for sharing your 5 Star Review and feedback on the HKS M40HL Super Fire Racing Spark Plug. We are glad to hear that they worked well for you with a custom tune. We agree that these should not be used unless running a tune. Thank you for the recommendation. Have a great day!

    Regards,

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