Ford PERFORMANCE 12MM 3V Spark Plugs for Performance Vehicles Mustang GT 12MM 3V Ford Racing Spark Plugs M-12405-3V12MM The 2008 and newer Ford Mustang/F-150 3V heads require 12MM Spark Plugs. Note: 2008 3V engines with late style 12 mm spark plugs can be identified by coil engineering number 8L3E. The... MSRP: Was: Now: $93.00