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This part is no longer available.
  • 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
Part Type
Electrical: Ignition Related
Warranty Availability
Not Available
Packaged Dimensions
6.25" x 4" x 4.5
Packaged Weight
1.1 lb(s)
UPC Code
Catalog Page Number
Country of Origin