{"product_id":"holley-efi-gen-iii-hemi-coil-harness-late-coils-558-311be","title":"Holley EFI Gen III HEMI Coil Harness: Chrysler 300 (05-15) \/ Dodge Ram 1500 (03-10)","description":"\u003ch3\u003eHolley EFI Coil Harness\u003c\/h3\u003e\u003cp\u003e2006 and Later Chrysler Gen III HEMI Engines\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003e558-311\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eOverview:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe Holley EFI Gen III HEMI Coil Harness is engineered specifically for late-model Gen III HEMI engines, providing a seamless connection for the advanced coil design introduced in 2006 and beyond. Chrysler’s Gen III HEMI engines transitioned from early coils requiring spark plug wires to a more modern coil design with integrated boots that connect directly to the spark plugs. This harness is tailored to support the later coil style, enabling precise control of fuel and spark through Holley EFI systems.\u003c\/p\u003e\u003cp\u003eDesigned for enthusiasts and professional tuners alike, this coil harness is ideal for those upgrading their Gen III HEMI with Holley EFI for enhanced engine management, whether for power upgrades, engine swaps, or forced induction applications. It delivers reliable, OEM-quality connections that ensure optimal performance and tuning flexibility.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eBuilt to complement Holley EFI’s advanced engine management capabilities, this coil harness offers numerous benefits for Gen III HEMI owners:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eCompatible with late Gen III HEMI coil packs that connect directly to spark plugs without spark plug wires\u003c\/li\u003e\n\u003cli\u003eEnables full control of fuel and spark timing through Holley EFI for precise tuning\u003c\/li\u003e\n\u003cli\u003eSupports power adders such as nitrous oxide, superchargers, turbos, and is compatible with methanol and water injection systems\u003c\/li\u003e\n\u003cli\u003eConstructed with TXL grade copper wiring for minimal weight and high temperature resistance\u003c\/li\u003e\n\u003cli\u003eFactory-style terminations and OEM-grade connectors ensure secure, positive fitment and reliable electrical connections\u003c\/li\u003e\n\u003cli\u003eWiring is routed through a split-loom braid for enhanced protection and a clean, professional appearance\u003c\/li\u003e\n\u003cli\u003eDesigned specifically for the Gen III HEMI engine platform to guarantee proper fit and function\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eConstruction \u0026amp; Design:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe Holley EFI coil harness is crafted with high-quality TXL copper wiring, known for its excellent conductivity and resistance to heat and abrasion. The wiring is sheathed in a durable high-temperature sleeve and routed through a split-loom braid, providing robust protection against engine bay hazards while maintaining a sleek, factory-like look. Each connector is OEM-grade, ensuring a precise fit that matches factory specifications, which minimizes installation issues and maximizes reliability.\u003c\/p\u003e\u003cp\u003eEvery aspect of the harness is engineered to meet the demanding environment of the Gen III HEMI engine bay, delivering long-lasting performance and durability under high heat and vibration conditions.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eInstallation \u0026amp; Fitment:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThis coil harness is designed for direct fitment on late Gen III HEMI engines equipped with the coil packs introduced in 2006 and later. Installation is straightforward, requiring no modifications to the engine or ignition system. The harness plugs directly into the factory coil connectors and spark plugs, simplifying the upgrade process for Holley EFI users.\u003c\/p\u003e\u003cp\u003eIt is essential to verify that your engine uses the late coil design without spark plug wires before purchasing. Reference the included image gallery to distinguish between early and late coil types to ensure compatibility.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat's Included:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eHolley EFI Gen III HEMI Coil Harness for late coil packs\u003c\/li\u003e\n\u003cli\u003eOEM-grade connectors pre-installed\u003c\/li\u003e\n\u003cli\u003eSplit-loom protective braid covering the wiring\u003c\/li\u003e\n\u003cli\u003eInstallation instructions and reference images\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eIdeal For:\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThis coil harness is perfect for Gen III HEMI owners looking to upgrade their ignition system with Holley EFI for improved tuning capabilities. It suits performance enthusiasts performing engine swaps, forced induction upgrades, or those seeking precise control over fuel and spark timing. Professional tuners and DIY builders alike will benefit from its plug-and-play design and robust construction.\u003c\/p\u003e","brand":"Holley EFI","offers":[{"title":"Default Title","offer_id":47315668369620,"sku":"558-311","price":179.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0660\/8542\/1268\/files\/3454_a480197708658eadf36649df3734b1ee4e80c8a2_2e9636aa-a439-4333-93ab-b9c6679e3e7e.webp?v=1766655092","url":"https:\/\/fasthemis.com\/products\/holley-efi-gen-iii-hemi-coil-harness-late-coils-558-311be","provider":"FastHemis","version":"1.0","type":"link"}