Swapping an LS engine requires a reliable fuel delivery system. We researched and compared the top fuel line kits on the market, evaluating manufacturer specifications, industry standards (SAE J30R9, AN fittings), and aggregated owner feedback to help you choose. Our picks range from budget-friendly to professional-grade, each with real limitations.
| Photo | Product | Score | Buy |
|---|---|---|---|
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Holley 12-847 Retro-Fit EFI Fuel Line Kit Best Overall Stainless steel braided hose with -6 AN fittings, 30 inches long |
9.2 | 🛒 Check Price |
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Russell Performance 640490 Fuel Line Kit Best for Custom Routing Nylon braided hose with -6 AN fittings, 10 feet roll |
8.8 | 🛒 Check Price |
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Aeromotive 16301 Stealth Fuel Line Kit Best for High Horsepower -8 AN stainless steel braided hose, 25 feet |
9.0 | 🛒 Check Price |
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Edelbrock 36710 Fuel Line Kit Best Budget Pick Rubber hose with -6 AN fittings, 3 feet |
8.2 | 🛒 Check Price |
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Summit Racing SUM-230030 Fuel Line Kit Best Value Kit Stainless braided hose with -6 AN fittings, 6 feet |
8.6 | 🛒 Check Price |
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Vibrant Performance 22551 Fuel Line Kit Best for Tight Spaces Nylon braided hose with push-lock fittings, 4 feet |
8.1 | 🛒 Check Price |
 |
Gates 27349 Fuel Line Kit Best OEM Replacement Style Rubber hose with quick-connect fittings, 36 inches |
7.8 | 🛒 Check Price |
1. Holley 12-847 Retro-Fit EFI Fuel Line Kit: Best Overall
In our evaluation, the Holley 12-847 stands out as a complete and hassle-free solution for LS swaps. It includes two pre-assembled hoses with -6 AN fittings, designed to connect the fuel rail to the hard lines. Based on owner feedback, installation is straightforward for those with basic mechanical skills. The stainless steel braided hose offers excellent durability and meets SAE J30R9 standards, ensuring compatibility with modern fuels.
However, the 30-inch hose length may not accommodate all vehicle layouts, particularly if you have a custom fuel rail location. It also lacks a fuel filter or regulator, so you will need to source those separately. This kit is best for builders who want a simple, reliable connection without fabrication. Skip it if you need longer hoses or a complete fuel system.
- Includes pre-assembled hoses and fittings for a straightforward install
- Compatible with most LS intake manifolds and fuel rails
- Meets SAE J30R9 standards for fuel injection systems
Pros: Complete kit with everything needed for a basic LS swap; High-quality stainless steel braided hose resists abrasion and corrosion
Cons: Hose length may be too short for some custom routing; No included fuel filter or pressure regulator
2. Russell Performance 640490 Fuel Line Kit: Best for Custom Routing
For builders who need to route fuel lines through unconventional paths, the Russell Performance 640490 offers maximum flexibility. The 10-foot nylon braided hose can be cut to exact length, and the included -6 AN fittings are reusable. Based on owner feedback, this kit is popular for custom LS swaps where space is tight. The hose meets SAE J30R9 standards and is compatible with ethanol-blended fuels.
However, the nylon braid is more prone to wear from rubbing against sharp edges, so protective sleeving is recommended. Assembly requires careful cutting and cleaning to avoid debris in the fuel system. This kit is ideal for experienced builders who want a custom fit. Skip it if you prefer a pre-assembled, no-cut solution.
- Sold as a 10-foot roll of hose with separate AN fittings
- Nylon braided hose is flexible and lightweight for tight spaces
- Fittings are reusable and can be assembled without special tools
Pros: Flexible hose allows custom routing in cramped engine bays; Fittings can be disassembled and reused
Cons: Requires cutting and assembly, which can be messy; Nylon braid is less abrasion resistant than stainless steel
3. Aeromotive 16301 Stealth Fuel Line Kit: Best for High Horsepower
The Aeromotive 16301 is engineered for high-horsepower LS swaps where fuel demand exceeds standard -6 AN capacity. The -8 AN hose and PTFE liner allow safe flow for forced induction or nitrous setups. In our evaluation, the build quality is exceptional, with crimped ends that eliminate the risk of leaks. Owner feedback confirms reliable performance in extreme conditions.
However, the fixed length and crimped ends limit customization; you cannot cut the hose to a shorter length. The price is also higher than most -6 AN kits. This kit is best for builders targeting 600+ hp who need a robust, high-flow fuel line. Skip it if you are building a mild street LS or need a custom-length hose.
- Supports up to 1000+ HP with -8 AN line size
- Includes PTFE liner for compatibility with all fuels including E85
- Hose ends are crimped for a permanent, leak-free connection
Pros: Handles high fuel flow for boosted or nitrous applications; PTFE liner resists ethanol and fuel breakdown
Cons: More expensive than -6 AN kits; Crimped ends mean the hose cannot be shortened or reused
4. Edelbrock 36710 Fuel Line Kit: Best Budget Pick
For budget-conscious builders, the Edelbrock 36710 provides a functional fuel line solution at a lower cost. It includes two rubber hoses with -6 AN fittings, ready to connect your fuel rail to hard lines. Based on owner feedback, it works well for low-horsepower LS swaps with stock fuel systems. The rubber hose is easy to route and install.
However, rubber hose is not as resistant to ethanol or high temperatures as braided stainless or PTFE. Some owners report swelling or cracking after extended use with E85. The 3-foot length may be too short for some engine bays. This kit is suitable for mild street builds on a budget. Skip it if you run E85 or need a long-lasting, high-performance line.
- Affordable option for basic LS fuel line connections
- Includes two pre-assembled hoses for supply and return
- Rubber hose is flexible but less durable than braided options
Pros: Very affordable compared to braided hose kits; Easy to install with pre-attached fittings
Cons: Rubber hose may degrade with ethanol fuels over time; Short 3-foot length limits routing options
5. Summit Racing SUM-230030 Fuel Line Kit: Best Value Kit
The Summit Racing SUM-230030 strikes a solid balance between affordability and performance. It provides 6 feet of stainless braided hose and four -6 AN fittings, enough for most LS swap fuel line runs. In our evaluation, the build quality is good for the price, and owner feedback highlights its reliability in daily-driven swaps. The hose meets SAE J30R9 standards.
However, the hose is relatively stiff, making it challenging to route in tight engine bays. Assembly requires careful cutting and installation of the fittings, which can be messy. This kit is ideal for builders who want a durable, stainless braided line without spending a premium. Skip it if you need a pre-assembled, ready-to-install kit or extremely flexible hose.
- Includes 6 feet of hose and 4 fittings for supply and return
- Stainless steel braid offers good durability at a moderate price
- Hose meets SAE J30R9 specifications
Pros: Good balance of quality and cost; Longer hose length than many kits in the same price range
Cons: Fittings are not pre-assembled; requires some assembly; Hose is stiffer than nylon braid, harder to route in tight spaces
6. Vibrant Performance 22551 Fuel Line Kit: Best for Tight Spaces
For tight engine bays where routing is a challenge, the Vibrant Performance 22551 offers a flexible and easy-to-install solution. The push-lock fittings simply push onto the hose without tools, making installation quick. Based on owner feedback, this kit is popular for LS swaps with limited space, such as in smaller cars. The nylon braided hose is lightweight and bends easily.
However, push-lock fittings require precise cutting and full insertion to avoid leaks; some owners report seepage if not installed correctly. The nylon braid is also more susceptible to abrasion and heat damage than stainless steel. This kit is best for builders who prioritize ease of installation and have a clean, well-protected routing path. Skip it if you need maximum durability or are running high fuel pressure.
- Push-lock fittings require no tools or clamps
- Nylon braided hose is lightweight and very flexible
- Includes 4 feet of hose and 4 push-lock fittings
Pros: Extremely easy to install with push-lock fittings; Flexible hose fits in cramped engine bays
Cons: Push-lock fittings may leak if not fully seated; Nylon braid is less durable than stainless steel
7. Gates 27349 Fuel Line Kit: Best OEM Replacement Style
The Gates 27349 is designed for those who want a fuel line that looks and functions like the OEM setup. It features a rubber hose with quick-connect fittings that snap into place, making installation simple. Based on our research, this kit works well for LS swaps that retain the factory fuel rail and hard lines. The rubber hose dampens fuel pump noise.
However, the rubber construction is not suitable for ethanol-blended fuels or high-temperature environments. The 36-inch length and specific fitting types may not match all LS swap configurations. This kit is best for a mild street swap where originality and ease of installation are priorities. Skip it if you use E85, have a high-horsepower build, or need a custom length.
- Uses factory-style quick-connect fittings for a stock look
- Rubber hose is quiet and doesn't transmit vibration
- Includes 36-inch hose with two quick-connect ends
Pros: Maintains a factory appearance; Quick-connect fittings are easy to install and remove
Cons: Rubber hose not recommended for E85 or high-heat applications; Limited length and specific fitting types may not fit all LS swaps
Frequently Asked Questions
What size fuel line is best for an LS swap?
For most naturally aspirated LS swaps under 500 hp, a -6 AN line is sufficient. For boosted or nitrous applications over 500 hp, a -8 AN line is recommended to ensure adequate fuel flow. We researched manufacturer guidelines and owner feedback, and -6 AN is the most common choice for street builds.
Can I use rubber fuel line on an LS swap?
Rubber fuel line can be used on low-horsepower, non-ethanol builds, but it is not recommended for E85 or high-heat applications. Based on industry standards, rubber hose degrades faster with ethanol and under high pressure. Stainless braided or PTFE-lined hose is more durable and safer for LS swaps.
Do I need a return fuel line on an LS swap?
Yes, most LS engines use a return-style fuel system. The factory fuel rail has a supply and return port. Aftermarket fuel line kits typically include both lines. If you are using a Corvette or truck regulator, you may need a return line. Check your specific fuel system requirements.
What AN fittings do I need for an LS swap?
Most LS fuel rails use -6 AN ORB (O-ring Boss) fittings for the supply and return. Some aftermarket rails use -6 AN male or female fittings. We recommend verifying your fuel rail and hard line fittings before purchasing a kit. Many kits include fittings that adapt to common LS rail sizes.
How long should the fuel line be for an LS swap?
The required length depends on your vehicle and routing. A typical LS swap in a muscle car or truck needs about 3-5 feet per line. We suggest measuring your specific routing from the hard line to the fuel rail. Most kits offer 3-6 foot hoses; custom routing may require a longer roll of hose.
Our Verdict
After researching and comparing specs, industry standards, and owner feedback, our top pick is the Holley 12-847 for its complete package and reliable performance in most LS swaps. For those needing custom routing, the Russell Performance 640490 offers flexibility. Choose based on your horsepower goals, fuel type, and installation preferences.
