--- product_id: 28286495 title: "Holley EFI Hp Ecu And Harness Ls1 & Ls6" brand: "holley" price: "€ 4732.13" currency: EUR in_stock: true reviews_count: 2 url: https://www.desertcart.sk/products/28286495-holley-efi-hp-ecu-and-harness-ls1-and-ls6 store_origin: SK region: Slovakia --- # Easy installation Vehicle specific fit Corrosion resistant Holley EFI Hp Ecu And Harness Ls1 & Ls6 **Brand:** holley **Price:** € 4732.13 **Availability:** βœ… In Stock ## Summary > πŸš€ Elevate Your Ride with Holley EFI! ## Quick Answers - **What is this?** Holley EFI Hp Ecu And Harness Ls1 & Ls6 by holley - **How much does it cost?** € 4732.13 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.sk](https://www.desertcart.sk/products/28286495-holley-efi-hp-ecu-and-harness-ls1-and-ls6) ## Best For - holley enthusiasts ## Why This Product - Trusted holley brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Built to Last:** Crafted from high-quality materials for durability. - β€’ **Hassle-Free Setup:** Enjoy a straightforward installation process. - β€’ **Quality You Can Trust:** Genuine Holley parts ensure reliability and performance. - β€’ **Tailored for Performance:** Designed specifically for your vehicle's needs. - β€’ **Unleash Your Engine's Potential:** Transform your LS1 & LS6 with precision tuning. ## Overview The Holley EFI Hp ECU and Harness for LS1 & LS6 is a top-tier performance upgrade designed for enthusiasts seeking reliability and precision. With its corrosion-resistant materials and vehicle-specific fit, this product promises easy installation and long-lasting durability, making it an essential choice for any serious automotive project. ## Description Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors powered every Monster Energy Nascar Cup team and nearly every NHRA Pro–Stock champion for four decades. Now, Holley EFI products power these cars and are dominating the performance world. Holley products for GM's popular LS engine are dominating the LS scene as well. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies we can give you the edge you need over the competition! ## Features - Genuine Holley Quality Parts - Corrosion resistant - Made from quality materials - Easy installation - Durable and long lasting - Fit type: Vehicle Specific ## Technical Specifications | Specification | Value | |---------------|-------| | Manufacturer | Holley | | Brand | Holley | | Model | Holley EFI Hp Ecu And Harness Ls1 & Ls6 | | Item Weight | 9 pounds | | Item model number | 550-602 | | Is Discontinued By Manufacturer | No | | Exterior | Machined | | Manufacturer Part Number | 550602 | | OEM Part Number | 550-602 | ## Images ![Holley EFI Hp Ecu And Harness Ls1 & Ls6 - Image 1](https://m.media-amazon.com/images/I/81GP2j+fcFL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ 5.0 out of 5 stars This deserves better than that one-star review. *by J***H on Reviewed in the United States on April 18, 2016* Just writing this to offset the 1 star of the other reviewer. To say that this is very badly made is to be dishonest, likely due to frustration with getting a car running (something I can relate to all too well), and that is unfair. After having initially bought a standalone from another vendor that was good-but-not-great I was frankly surprised at how well this harness was made. I do wish some of the wires were about 2-3 inches longer, but that is more a result of my routing choices and less a fault of the system (I'm going to add an extension or two later). The wires are of good quality, the loom is nice and all the ends are well-wrapped and secure. It even comes with an O2 sensor.Install was fairly easy and I had my old harness out and this one in in a few hours. Setup was a bit confusing at first but I have zero experience with tuning, though once I took it upon myself to learn a bit about how fuel systems actually work and what the various terminology meant it wasn't that hard to get at least semi-proficient. But again, that is to be expected; if you don't know what you're doing then no tool will be of any help to you.So, some pros - It's pretty universal, some adapters might be needed here or there during an engine swap but that's not a surprise. It's not much more expensive than a good PSI harness + a tune. It doesn't require fees or licenses to use like some products do. It's easy to plug in a laptop and play around with it, plus you get to keep the various profiles yourself. Holley forums and tech support are also pretty good about helping you.Some cons - It's not cheap. Some of the wires could be a bit longer. The labeling of the wires is nice, but not very permanent. I wish the power wire were a few feet longer. I wish the midline fuses were either closer to or farther away from the computer, as it is they are in an awkward place [for my setup (71 Chevelle with computer above glove box and harness going through vent, the fuses are down in the vent)], but I'm planning to move it and go through firewall so this could change.Overall though, this product, like most Holley products (except their early LS swap headers, which aren't ideal) is a solid choice assuming you can spare the $$$. Their AC bracket for LS motors is also top-notch and worlds better than any of the hundreds of 2-sheets-of-steel-connected-by-spacers designs floating around. ### ⭐ 1.0 out of 5 stars harness very badly made. *by A***D on Reviewed in the United States on February 4, 2014* This is the worst wiring harness I avtrust regrst. spending my money on this bad harness . First no power going to injectors and Sparks wirs going to the rely is mixed up. Now can't start the engine i don't now why. can't trust the product.This engine was running with my previous harness and ECU setup on the same car!!! --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.sk/products/28286495-holley-efi-hp-ecu-and-harness-ls1-and-ls6](https://www.desertcart.sk/products/28286495-holley-efi-hp-ecu-and-harness-ls1-and-ls6) --- *Product available on Desertcart Slovakia* *Store origin: SK* *Last updated: 2026-05-19*