PLEASE NOTE: All HKS Spark Plugs Are Sold Individually – Please Purchase The Amount Needed For Your Car.
- Thread Size: 14×19mm
- Wrench Size: 16mm
- Heat Range: NGK #7
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 EnginesRotary 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.