GSS315 255 Liter Per Hour Fuel Pump: The Ultimate Guide for High-Performance Fuel Delivery

The bottom line: The GSS315 255 liter per hour fuel pump is a high-flow, reliable upgrade for vehicles that need more fuel, especially those with modified engines, turbochargers, or superchargers. It delivers a consistent 255 liters per hour (about 67 gallons per hour) at 43 PSI, making it a popular choice for street and race applications. This guide explains what this pump does, who needs it, how to install it, and why it’s a smart investment.

What is the GSS315 255 LPH Fuel Pump and Why Does It Matter?

The GSS315 is a direct replacement or upgrade fuel pump designed for a wide range of vehicles. It’s known for its ability to push a high volume of fuel—255 liters per hour—under pressure. This is critical for engines that demand more fuel than stock pumps can provide. If your car is running lean, losing power at high RPMs, or you’ve added performance parts like a bigger turbo, injectors, or a tune, the stock fuel pump may not keep up. The GSS315 solves that problem.

Key Features of the GSS315 255 LPH Pump

  1. High Flow Rate: 255 liters per hour at 43 PSI is the standard rating. This supports up to 500-600 horsepower on naturally aspirated engines and up to 400-500 horsepower on forced induction setups, depending on fuel type (gasoline, E85, etc.).
  2. Universal Fit: It’s a compact, in-tank design that fits many fuel modules. A universal mounting kit is often included, making it adaptable to many vehicles.
  3. Reliable Performance: It’s built with a turbine-style impeller, which runs quietly and lasts longer than older vane-style pumps. It’s also compatible with modern fuels, including ethanol blends.
  4. Easy Installation: Most installations are straightforward. You remove the old pump, install the new one with the included hardware, and reconnect the wiring. No special tools are usually needed.

Who Needs a GSS315 255 LPH Fuel Pump?

  1. Performance Enthusiasts: If you’ve added a turbo, supercharger, or nitrous, your engine needs more fuel. The GSS315 ensures you don’t run lean under boost.
  2. Daily Drivers with Mods: Even a mild tune or intake upgrade can push a stock pump to its limit. This pump adds a safety margin.
  3. Off-Road and Racing Vehicles: High-RPM operation and long WOT pulls demand consistent fuel pressure. The GSS315 delivers.
  4. Replacement for Failing Pumps: If your stock pump is dying, this is a cost-effective upgrade that often costs less than a dealer replacement.

How to Install the GSS315 255 LPH Fuel Pump: A Step-by-Step Guide

Important: Always disconnect the battery negative cable before starting. Fuel is flammable, so work in a well-ventilated area and avoid sparks.

Step 1: Remove the Fuel Pump Module

  • Access the fuel tank. On most cars, this means removing the rear seat cushion or a access panel under the trunk carpet. On some vehicles, you may need to drop the tank.
  • Disconnect the fuel lines and electrical connectors from the top of the module.
  • Use a special tool (or a hammer and flathead screwdriver) to loosen the locking ring. Turn it counterclockwise.
  • Lift the module out of the tank. Be careful not to damage the float arm or strainer.

Step 2: Replace the Pump

  • Remove the old pump from the module housing. This often involves removing a retaining clip, spring, or rubber boot.
  • Transfer the old pump’s strainer (sock) to the new GSS315 pump. If the new pump comes with a strainer, use that.
  • Attach the new pump to the module. Make sure the orientation matches the old one. Secure it with the included hardware.
  • Reconnect the electrical wires. Many pumps use a simple plug-and-play connector. If yours doesn’t, use the included wire connectors and splice them correctly.

Step 3: Reinstall the Module

  • Lower the module back into the tank. Make sure the float arm doesn’t bind.
  • Install the locking ring by hand, then tighten it with the tool. Do not overtighten.
  • Reconnect the fuel lines and electrical connectors.
  • Reconnect the battery.

Step 4: Test the System

  • Turn the key to the “ON” position (but don’t start) for 2 seconds. Repeat 3-4 times. This primes the system.
  • Check for any fuel leaks around the connections.
  • Start the engine. Listen for a quiet hum from the pump. Let it idle for a few minutes.
  • If the engine runs fine, you’re done. If it sputters, you may have a leak or a wiring issue.

Common Mistakes to Avoid

  1. Using the Wrong Voltage: The GSS315 is designed for 12V, but some older cars have a voltage drop. Check your battery and alternator health.
  2. Forgetting the Strainer: Never run a pump without a strainer. Dirt will ruin it quickly.
  3. Incorrect Wiring Polarity: The pump will run backward if you reverse the wires. It won’t pump fuel. Double-check the color codes.
  4. Not Priming the System: Starting the engine without priming can cause the pump to run dry, damaging it.
  5. Overtightening the Locking Ring: This can crack the plastic module. Tighten it snug but not gut-wrenching.

How to Tell if Your GSS315 Pump is Failing

Symptoms of a failing fuel pump include:

  • Engine sputters or hesitates at high RPM.
  • Hard starts, especially when the tank is low.
  • Whining noise from the gas tank area.
  • Loss of power under load.
  • Check engine light with a code for fuel pressure or fuel trim.

If you experience any of these, test the fuel pressure with a gauge. It should be within 3-5 PSI of the rated pressure (43 PSI at idle). If it’s lower, the pump may be clogged, worn, or failing.

GSS315 vs. Other Fuel Pumps: What’s the Difference?

  • GSS315 vs. GSS340: The GSS340 flows 340 LPH, which is for higher horsepower (up to 700+). The GSS315 is better for mild to moderate builds.
  • GSS315 vs. GSS250: The GSS250 is an older design with lower flow. The GSS315 is a more reliable, modern upgrade.
  • GSS315 vs. Stock Pump: Stock pumps are typically rated for 150-200 LPH. The GSS315 is a significant upgrade without breaking the bank.

Maintenance Tips for Long Life

  • Keep the Tank Full: Running low on fuel can cause the pump to overheat and suck in debris.
  • Change the Fuel Filter Regularly: A clogged filter can strain the pump.
  • Use Quality Fuel: Bad gas can deposit varnish on the pump internals.
  • Listen for Changes: If the pump gets louder, it’s time to check it.

Why Choose KEMSO for Your Fuel Pump Needs?

If you're looking for a reliable, high-performance fuel pump that doesn't compromise on quality, consider the KEMSO brand. KEMSO fuel pumps are designed as OEM replacements that meet or exceed original equipment specifications. They are built with high-quality materials for long-lasting performance. Best of all, every KEMSO fuel pump comes with a lifetime warranty, giving you peace of mind. Whether you need a pump for a car, motorcycle, or watercraft, KEMSO offers a wide range of options. For more information on KEMSO products and to find the perfect pump for your vehicle, visit their official website. You can browse their entire selection, read customer reviews, and take advantage of their lifetime warranty guarantee.

Final Thoughts

The GSS315 255 liter per hour fuel pump is a proven, affordable upgrade for anyone who needs more fuel. It’s easy to install, reliable, and supports a wide range of performance levels. Whether you’re building a track car, a daily driver, or an off-road rig, this pump is a solid choice. Just remember to follow the installation steps carefully, maintain your fuel system, and you’ll enjoy years of trouble-free performance.

For more information and to purchase a high-quality fuel pump with a lifetime warranty, visit https://www.kemsoracing.com/.


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