NGK LTR7IX-11 (6510) Iridium Spark Plugs – One Step Colder, Pre-Gapped .026" – Fiesta ST 1.6L EcoBoost (Set of 4)

One step colder iridium plugs, gapped and ready to install.

The NGK Iridium IX LTR7IX-11 (stock #6510) is the go-to one-step-colder plug for the 1.6L EcoBoost Fiesta ST. NGK ships them at .044". We gap every set to .026" before it ships, so they go straight in the car.

Why one step colder? A colder plug pulls heat out of the tip faster, which helps prevent pre-ignition when you add boost, timing, or ethanol. It’s the standard upgrade once you’re tuned.

Built for ethanol and boost: a perfect match for our Focus ST coil pack conversion kit on stock-turbo and big-turbo Fiesta STs running E30 to E85.

Specs

• NGK part: LTR7IX-11, stock #6510
• Heat range: 7 (one step colder than stock)
• Gap: .026", pre-set by SVTDF
• Iridium center electrode, 14mm thread, 5/8" hex
• Set of 4

Fits: 2014–2019 Ford Fiesta ST 1.6L EcoBoost

Don’t overtorque, and always run the plug gap your tuner recommends.