Ford Racing ignition coil sets are direct replacements for 4.6L 3V engines equipped with 8L3E coils. These coils fit Mustang 4.6L 3V engines with 12mm spark plugs and are required when installing certain Ford Racing heads on Mustang GTs originally equipped with "high thread" designs. Fit your vehicle with the right ignition coil sets designed by the original maker--Ford Racing--and rest assured that the performance will be accurate.