HKS Iridium Super Fire Racing 50003-M40iL Spark Plug Long Reach NGK # 8 Heat Range 14mm × 26.5mm

Ultimate spark plug "M".

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

• 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.