 The Iridium electrode is more suitable for tuned engines due to the iridium electrode having a high melting point (2454°C) when compared to platinum (1769°C).
- The iridium electrode can withstand prolonged usage due to its high heat resistance whilst still being able to utilize a thinner electrode design (4mm). The advantage of having a thinner electrode is an increase in charge density. This allows the spark to be more effective at high boost pressures and high rpm.
- The earthing electrode on the HKS spark plug is grooved to focus the spark within a smaller area. This promotes charge intensity which in turn produces improved combustion efficiency.
- The plug is chrome coated giving it a corrosion resistant surface and improved appearances.
- Spark plug design for rotary engines (RE Series) and Super Fire Racing Pro plugs ( R/R-I Series) utilizes a super fine platinum grounding electrode. The electrode is designed to withstand extreme racing condition. Compared to mainstream plug design, the electrode does not contain any bends thus eliminating any possibility of crack failure within the bend.
Spark Plug Heat Range Selection
A Spark plugs heat range is an indication of its heat dissipation ability. For HKS part codes, the S** number indicates the heat range, with S30 having the lowest heat dissipation and S55 having the highest.
Ideal heat range selection is apparent when spark plug operating temperature is between 500°C and 900deg C. If operating temperature falls below 500°C, plug carbon fouling will occur indicated by black deposits on the plug. If operating temperature climbs above 900°C, then pre-ignition (detonation) caused by the plug may occur. |