HKS Super Fire Racing M40G Spark Plug

Important Note: All HKS Spark Plugs Are Sold Individually - Please Purchase The Amount Needed For Your Car.

G Type

Thread Size: 14×19mm

Wrench Size: 20.8mm

Heat Range: NGK #8

Ultimate spark plug "M".

Ignitionability, durability, anti-insulation all reinforced. HKS has made the best plug for both tuning engines and stock engines.

Features

• 0.6mm Iridium Alloy Center Electrode
  Iridium Alloy Center Electrode reduces voltage requirement as well as improving ignition performance and durability.
• Outer Electrode with Platinum Chip
  The Outer Electrode incorporates a square platinum chip which improves durability, and when combined 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 various combustion conditions carbon buildup can occur causing misfires. The Thermal Edge of the ceramic insulator will discharge to help decrease carbon deposits.
• Spark Support Gap
  Discharges will occur in the Spark Support Gap (space between the tip of insulator and the base of the outer electrode) to help prevent carbon buildup.
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• 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 improves durability, which allows for use under hard combustion conditions like continuous high load during circuit driving or aggressive tuning.
    * Improper combustion condition and wrong heat range selection might 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.

  Special Design RE-type for Rotary Engines

  Rotary engines reciprocating design have a different mechanism and combustion condition. RE-type spark plugs are specially designed to meet the different requirement for rotary engines. The straight shape platinum outer electrode enables reliable ignition performance.

  
  

  ■Heat Range Conversion Chart

  HKS	25	30	35	40	45	50	52.5	55
  DENSO	16	20	22	24	27	31	32	34
  NGK	5	6	7	8	9	10	10.5	11

  * Above information is the reference for heat resistance.