In stock
SKU: 556-163
Regular price $594.95

Product details

  • Type Ignition Coils
  • Vendor Holley
  • SKU 556-163
These Holley EFI Smart Coils are a bolt-in ignition upgrade for your late model HEMI or Coyote engine. Here's the difference over a stock coil; they produce more spark energy while consuming less power without sacrificing voltage output. This means you get hotter spark at the plug to burn the maximum amount of fuel in each cylinder while using less power from your electrical system. For Hemi combinations currently using Holley EFI or Terminator X, use Smart Coil Ignition Harnesses 558-312 & Coil Extension Harnesses 558-326 for a plug and play solution.


  • Direct bolt-on to factory valve covers
  • Same wiring pinout as other IGN-1A coils for easy plugin upgrades (Will not work with factory wiring)
  • More spark energy than any other smart coil on the market for maximum fuel burn during combustion sequence
  • Low current draw means less demand on the electrical and charging system
  • Built-in ignitor for compatibility with Holley EFI and many other aftermarket ECU’s
  • Maximum operating voltage of 18 volts – for compatibility with both 12 volt and 16 volt electrical systems found in many performance/race applications