We recommend using the Brisk racing GR14YS in place of this plug on '07-'12 GT500 running less than 18 PSI of boost. We recommend the Brisk Racing GR12S in place of these on '13-'14 GT500's and '07-'12 GT500's that are running greater than 18 PSI.

Set of 8 colder spark plugs for a forced induction application, must be gapped at .035"" -.032""

NGK Iridium TR-7-IX

The Spark Plug Serious Enthusiasts Rely On

Designed specifically for the performance enthusiast. Iridium IX offers extreme ignitability, improved throttle response and superior anti fouling

• Fine Iridium tip ensures high durability and a consistently stable spark
• Iridium alloy has extremely high melting point, perfect for today s high-tech, high-performance engines
• Trivalent Metal Plating - superior anti-corrosion and anti-seizing properties
• Outstanding acceleration, high fuel efficiency and durability
• Ultimate design, technology and performance.