Description

• Fits 2005-2008 3V heads requiring the 16 mm thread
• For use in engines with higher than stock cylinder combustion pressures or sustained high rpm
• Unique design is proprietary to Ford 3-valve engines
• One heat range colder than the stock Mustang GT plug
• Two heat ranges colder than the stock 5.4L-3V truck engine plug
• Sold in engine sets of 8
• Use M-12405-3V12MM spark plugs for 2008 and newer 3V heads
• Note:
  • 2008 engines with late style 12 mm spark plugs can be identified by coil engineering number 8L3E
  • 2005-2008 engines with early style 16 mm “High Thread” design spark plugs can be identified by coil engineering number 3L3E part number
  • All 2009-2010 engines use 12 mm spark plugs