Swapping an LS engine into your vehicle is a popular upgrade, offering significant performance gains. However, a crucial aspect often overlooked is the fuel system. The stock fuel pump in many donor cars may not be sufficient for the increased demands of a high-performance LS engine. This is where an external fuel pump kit comes into play. This comprehensive guide explores the benefits, components, and installation of an LS swap external fuel pump kit.
Why Use an External Fuel Pump Kit for Your LS Swap?
Using an external fuel pump offers several advantages over relying on the original in-tank pump, particularly in high-performance LS swaps:
- Increased Fuel Flow: LS engines, especially modified ones, require significantly higher fuel flow rates than many stock systems can provide. An external pump delivers the necessary volume to prevent fuel starvation under high demand.
- Higher Fuel Pressure: External pumps can maintain consistent and accurate fuel pressure, crucial for optimal engine performance and fuel delivery. This is especially important with forced induction applications (turbochargers or superchargers).
- Improved Reliability: External pumps are easier to access and maintain, reducing downtime in case of failure. In-tank pumps can be challenging and expensive to replace.
- Flexibility & Scalability: External pumps offer easier modification and upgrades should your performance goals change. You can upgrade to a higher-flow pump relatively easily without extensive tank modifications.
- Protection from Debris: In-tank pumps are susceptible to damage from debris in the fuel tank. An external pump sits outside the tank, shielded from this potential source of failure.
Components of a Typical LS Swap External Fuel Pump Kit:
A complete kit usually includes the following components:
- High-Flow Fuel Pump: The core component, chosen based on the desired horsepower and fuel requirements of your LS engine setup. Consider the pump's flow rate (gallons per hour or liters per hour) and pressure capabilities (PSI).
- Fuel Pump Mounting Bracket: Provides a secure and stable mounting point for the pump.
- Fuel Filter: Essential for protecting the pump from debris and ensuring clean fuel delivery.
- Fuel Lines & Fittings: Connect the pump to the fuel tank and engine. These need to be sized appropriately to handle the increased fuel flow.
- Pressure Regulator: (Often included, but sometimes sold separately) Maintains consistent fuel pressure at the rail, ensuring proper fuel delivery regardless of engine demand.
- Wiring Harness: Provides power to the fuel pump and may include a relay for improved reliability.
Choosing the Right Fuel Pump:
Selecting the correct fuel pump is critical. Factors to consider include:
- Engine Horsepower: The higher the horsepower, the higher the flow rate required.
- Fuel Type: Ensure the pump is compatible with your fuel (gasoline, E85, etc.).
- Pressure Rating: Choose a pump that can deliver sufficient pressure for your fuel injectors.
- Pump Style: Different pump styles (e.g., in-line, submersible) have various advantages and disadvantages.
Installation Considerations:
Installing an external fuel pump kit requires mechanical aptitude and careful planning. Consult a professional if you're unsure about any aspect of the installation process. Properly grounding the pump is essential to avoid electrical issues. Always ensure the fuel lines are securely connected to prevent leaks. Accurate fuel pressure regulation is crucial for optimal engine performance and longevity.
Conclusion:
Upgrading your fuel system with an external fuel pump kit is a smart investment for any LS engine swap, particularly those pushing higher horsepower levels. By carefully selecting the right components and following the installation instructions, you can ensure a reliable and efficient fuel delivery system that will support your engine's performance potential. Remember to consult your specific kit's instructions for detailed installation steps and safety precautions.
