Upgrading your vehicle’s fuel pump is a popular modification for enthusiasts looking to squeeze more horsepower out of their engine. But before you dive into this project, it’s important to understand how a fuel pump works, why upgrading it matters, and what steps you’ll need to take to ensure a safe and effective upgrade. Let’s break it down in simple terms.
First, let’s talk basics. Your fuel pump’s job is to deliver fuel from the gas tank to the engine at the right pressure and volume. Stock fuel pumps are designed to handle the factory horsepower and torque output. If you’ve added performance mods like a turbocharger, supercharger, or even a high-flow exhaust system, your engine might be demanding more fuel than the stock pump can supply. This is where an upgraded fuel pump comes into play. A higher-capacity pump ensures your engine gets the fuel it needs to avoid lean conditions (too much air, not enough fuel), which can lead to overheating or even engine damage.
**Choosing the Right Fuel Pump**
Not all fuel pumps are created equal. When shopping for an upgrade, focus on three factors: flow rate, pressure, and compatibility. Flow rate is measured in liters per hour (LPH) or gallons per hour (GPH). Higher horsepower engines require pumps with higher flow rates. For example, a 500-horsepower engine typically needs a pump that can deliver at least 255 LPH. Pressure, measured in pounds per square inch (PSI), must also align with your fuel system’s requirements. Too much pressure can overwhelm your fuel injectors, while too little won’t meet your engine’s needs.
Compatibility is another biggie. Check whether your vehicle uses a in-tank pump, an external pump, or a dual-pump setup. Many modern cars have in-tank pumps, which are quieter and cooler-running but harder to access. Brands like Kemso Racing offer direct-fit upgrades for specific models, saving you time on modifications.
**Installation Tips**
Upgrading a fuel pump isn’t a plug-and-play job for most people. If you’re doing this yourself, safety is priority number one. Fuel systems are pressurized, so relieve pressure by disconnecting the fuel pump fuse and running the engine until it stalls. Disconnect the battery to avoid sparks, and have a fire extinguisher nearby—better safe than sorry.
For in-tank pumps, you’ll need to drop the fuel tank or access the pump through a hatch under the rear seats (common in some sedans). Clean the area thoroughly before opening the tank to prevent debris from contaminating the fuel system. When installing the new pump, replace the fuel filter and inspect the wiring for wear. If your pump comes with a new sending unit, make sure the float arm is adjusted correctly to avoid inaccurate fuel gauge readings.
**Tuning and Supporting Mods**
A high-flow fuel pump alone won’t magically add horsepower. It’s part of a larger system. For example, if your pump delivers more fuel but your injectors can’t keep up, you’ll hit a bottleneck. Consider upgrading injectors, adjusting the fuel pressure regulator, or tuning the engine control unit (ECU) to optimize air-fuel ratios. Many modern cars use electronic pressure regulators, so a professional tune might be necessary to unlock the pump’s full potential.
**Maintenance After Upgrading**
A performance fuel pump can handle more stress, but it’s not invincible. Regularly inspect the pump for signs of wear, like unusual whining noises or inconsistent fuel pressure. If you’re running ethanol-blended fuels (like E85), ensure your pump is compatible, as ethanol can degrade certain materials over time. Also, keep your fuel tank at least a quarter full to prevent the pump from overheating—submerged pumps rely on fuel for cooling.
**Common Pitfalls to Avoid**
One mistake people make is overspending on a pump that’s way beyond their needs. A 400 LPH pump might sound impressive, but if your setup only requires 280 LPH, you’re wasting money and risking pressure issues. Another pitfall is skipping the supporting mods. Think of your fuel system as a chain—every link (pump, injectors, regulator, tune) needs to work in harmony.
Lastly, don’t ignore the electrical side. High-performance pumps often draw more current, so check if your wiring harness or relay needs an upgrade. Voltage drop due to undersized wiring can reduce pump efficiency, leaving you with less flow than advertised.
**Final Thoughts**
Upgrading your fuel pump is a smart move if you’re chasing horsepower, but it’s not a standalone fix. Do your research, match the pump to your goals, and invest in complementary upgrades. Whether you’re building a track monster or just want a bit more pep on the street, a well-chosen fuel pump ensures your engine stays fed and happy. And remember, when in doubt, consult a trusted mechanic or performance shop—they’ll help you avoid costly mistakes and keep your project running smoothly.