Holley EFI Gen III Hemi Smart Coils

Fits Most HEMI and Coyote Engines

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Overview:

The Holley EFI Gen III Hemi Smart Coils are a premium ignition upgrade designed specifically for late model HEMI and Coyote engines. These coils deliver a significant improvement over stock ignition coils by producing more spark energy while drawing less electrical power. This combination results in a hotter, more efficient spark at the plug, which enhances combustion and maximizes fuel burn in each cylinder. Ideal for enthusiasts and racers looking to optimize ignition performance, these smart coils integrate seamlessly with Holley EFI and Terminator X systems for a reliable, plug-and-play upgrade.

Whether you’re upgrading your street machine or building a high-performance race engine, these smart coils provide a robust ignition solution that supports both 12-volt and 16-volt electrical systems commonly found in performance and racing applications.

Key Features:

Holley EFI Gen III Hemi Smart Coils offer advanced technology and thoughtful engineering to improve ignition performance and reliability. Key features include:

• Direct bolt-on design to factory valve covers for easy installation
• Same wiring pinout as other IGN-1A coils, enabling straightforward plugin upgrades (note: not compatible with factory wiring)
• Delivers more spark energy than any other smart coil on the market, ensuring maximum fuel burn during combustion
• Low current draw reduces demand on the electrical and charging system, improving overall vehicle reliability
• Built-in ignitor compatible with Holley EFI and many aftermarket ECUs for versatile integration
• Maximum operating voltage of 18 volts supports both 12-volt and 16-volt electrical systems
• Designed specifically for late model HEMI and Coyote engines, making it an ideal upgrade for these popular platforms

Construction & Design:

Holley EFI smart coils are engineered with high-quality materials and precision manufacturing to ensure durability and consistent performance under demanding conditions. The coils feature robust internal circuitry that optimizes spark energy output while minimizing electrical load. Their direct bolt-on design matches factory valve cover mounting points, maintaining a clean and professional engine bay appearance. The integrated ignitor simplifies wiring and ensures reliable operation with Holley EFI systems and compatible aftermarket ECUs.

Installation & Fitment:

Installation is straightforward thanks to the direct bolt-on design that fits factory valve covers on most late model HEMI and Coyote engines. These smart coils share the same wiring pinout as other IGN-1A coils, allowing for easy plug-and-play upgrades when paired with Holley EFI or Terminator X systems. For a seamless installation, Holley recommends using Smart Coil Ignition Harnesses (part #558-312) and Coil Extension Harnesses (part #558-326). Note that these coils will not work with factory wiring harnesses, so proper harnesses are essential for compatibility.

What's Included:

• Holley EFI Gen III Hemi Smart Coils (set)
• Installation instructions (where applicable)

Ideal For:

These smart coils are perfect for enthusiasts and professional builders upgrading late model HEMI or Coyote engines who want improved ignition performance without increasing electrical system load. They are especially well-suited for vehicles running Holley EFI or Terminator X engine management systems and those operating in high-performance or racing environments where reliable, powerful spark energy is critical.

Holley EFI delivers standalone engine management and EFI systems built for everything from engine swaps to serious horsepower builds. With platforms like Sniper, Terminator X, HP, and Dominator, Holley EFI is aimed at enthusiasts who want modern tuning control, data, and drivability—whether it’s a street car, track car, or full-on race program.