GM LS Return Style Fuel System Plumbing Kit
WA01021
This GM LS Return Style Fuel System Plumbing Kit provides everything needed to properly plumb a return-style fuel system for your LS swap, rock crawler, buggy, or off-road race rig. This kit features a Walbro 255 LPH fuel pump, an industry standard known for consistently delivering high pressure flow to support up to 500+ HP, and high quality Fragola fittings and premium nylon race hose. The lightweight, flexible hose is significantly easier to route than traditional stainless braid and is fully compatible with modern pump gas and ethanol blends.
Included Components:
- (6) -6 AN Straight Fittings
- (3) -6 AN 90° Fittings
- (1) 3/8" Quick Disconnect to -6 AN Straight Fitting
- (1) 5/16" Quick Disconnect to -6 AN Straight Fitting
- (1) Walbro 255 LPH Fuel Pump with Sleeve & Clamps
- (2) Pump Fitting to -6 AN
- (1) Fragola 10 Micron Premium Post Filter with -6 AN Fittings
- (30 ft) -6 AN Premium Nylon Race Hose
Specifications
- Fuel System Type: Return Style
- Application: GM LS Engines
- Hose Size: -6 AN
- Hose Length: 30 Feet
- Fuel Pump Flow Rating: 255 Liters Per Hour
- Post Filter Rating: 10 Micron
- Fitting Brand: Fragola Performance Systems
- Hose Type: Premium Nylon Race Hose
Fitment
- Designed for GM LS return-style fuel systems
- Ideal for:
- LS swaps
- Tube chassis buggies
- Rock crawlers
- Ultra4 builds
- Custom off-road applications
Note: Not intended for returnless factory fuel systems without proper conversion.
Tech Insight
1. What is a return-style LS fuel system?
A return-style LS fuel system continuously circulates fuel from the fuel tank to the engine and back to the tank through a dedicated return line. Unlike a returnless system, fuel pressure is controlled by an external fuel pressure regulator near the engine. This design provides more consistent fuel pressure and is commonly used on high-performance LS engines, off-road vehicles, race cars, and custom LS swaps.
2. What LS fuel rails does this kit work with?
This kit is designed for GM LS fuel rails that require both a supply line and a return line. It works with many factory LS fuel rails as well as aftermarket LS fuel rails that utilize a return-style fuel system configuration. If you're unsure about your fuel rail setup, contact us and we'll help determine the correct plumbing kit for your build.
3. What fuel pressure regulator is included in this kit?
The kit includes an adjustable return-style fuel pressure regulator designed to maintain consistent fuel pressure under varying engine loads. The regulator returns excess fuel to the tank while supplying the engine with the fuel pressure required by most GM LS engine combinations.
4. Is the included fuel pump suitable for an LS swap?
Yes. The included Walbro 255 LPH fuel pump is one of the most commonly used LS swap fuel pump options available. It provides reliable fuel delivery for naturally aspirated LS engines and many moderate-performance combinations while offering proven durability in off-road and racing applications.
5. What are the benefits of a return-style fuel system compared to a returnless system?
A return-style system offers greater fuel pressure control, improved tuning flexibility, and more stable fuel delivery under high-demand conditions. This makes it a popular choice for modified LS engines, forced induction applications, race vehicles, and off-road builds where consistent fuel pressure is critical.
6. Is this fuel system suitable for turbocharged or supercharged LS engines?
This kit is ideal for naturally aspirated LS engines and moderate-performance builds. Higher horsepower turbocharged, supercharged, or race-only combinations may require larger fuel pumps, increased hose sizes, larger injectors, and additional fuel system upgrades. Contact us if you're building a high-horsepower LS engine and need assistance selecting the proper fuel system components.
