When pushing your high-performance engine to its limits, a standard fuel pump simply won’t cut it. Upgrading to a high-flow unit is essential for delivering the consistent fuel volume and pressure needed to support significant horsepower gains, whether you’re running on pump gas, E85, or racing fuel. The right pump ensures your air/fuel ratio stays optimal, preventing dangerous lean conditions that can lead to engine damage under boost or at high RPM.
This roundup focuses on 340 to 400 LPH (liters per hour) in-tank fuel pumps, a popular category for builds ranging from aggressive street machines to dedicated race cars. We’ve compiled a list of top-tier options from trusted manufacturers, highlighting their key features, compatibility, and what makes each one a strong contender for your next performance upgrade. Finding the perfect balance of flow, durability, and fuel compatibility is key to unlocking your engine’s true potential.
Our Top Picks for High-Flow Fuel Pumps
- KEMSO 340LPH High Performance Fuel Pump
- AEM 50-1215 E85-Compatible High Flow Fuel Pump
- AEM 50-1000 High Flow In-Tank Fuel Pump
- AEM 50-1220 E85-Compatible High Flow Fuel Pump
- QFS 340LPH E85/Flex In-Tank Performance Fuel Pump
- Walbro 400 LPH High Flow In-Tank Fuel Pump
- AEM 380 LPH High Flow In-Tank Fuel Pump
- DeatschWerks DW300 340 LPH In-Tank Fuel Pump
KEMSO 340LPH High Performance Fuel Pump
The KEMSO 340LPH pump is a robust direct replacement for popular models like the Walbro GSS340, making it an accessible upgrade for many vehicles. It is engineered to support engines producing up to 600 brake horsepower across a wide range of applications, including naturally aspirated, turbocharged, and supercharged setups. This makes it a versatile choice for enthusiasts looking for a significant power increase.
Built for modern fuel demands, this pump is fully compatible with both standard gasoline and E85 flex fuel. A notable benefit is the direct access to USA-based technical support, providing peace of mind and assistance during installation or troubleshooting. Its design prioritizes reliable flow and pressure to meet the needs of demanding high-performance driving.
AEM 50-1215 E85-Compatible High Flow In-Tank Fuel Pump
AEM’s 50-1215 fuel pump is a high-performance unit designed specifically for in-tank use in forced induction and high-output naturally aspirated vehicles. Its standout feature is its extensive fuel compatibility, being tested and verified to work with ethanol blends up to E100 (pure ethanol), methanol up to M100, and all types of gasoline. This makes it an ideal pump for racers and enthusiasts who frequently use alternative fuels.
Every single pump is flow-tested at 40 PSI to guarantee it meets the 340 LPH specification before leaving the factory, ensuring consistent performance and quality. The kit is comprehensive, including a wiring harness, pre-filter, and necessary O-rings for a straightforward installation. This attention to detail and validation provides a high level of confidence for critical engine applications.
AEM 50-1000 High Flow In-Tank Fuel Pump
The AEM 50-1000 is a high-flow 340 LPH fuel pump engineered for high-output EFI vehicles. It shares the same rigorous testing standards as other AEM pumps, with each unit verified to flow 340 LPH at 40 PSI. Its 39-millimeter diameter and offset inlet design are intended to simplify installation in a wide array of vehicle applications, offering broad compatibility.
This model is designed primarily for gasoline use, and AEM notes that pump life may be reduced if used consistently with E85 fuel. The kit is well-appointed, including the pump, a rubber sleeve, end caps, a pre-filter, hose, clamps, and a flying lead for electrical connection. It represents a solid, reliable choice for performance builds that will primarily run on gasoline.
AEM 50-1220 E85-Compatible High Flow In-Tank Fuel Pump
Similar to the 50-1215, the AEM 50-1220 is a 340 LPH high-flow pump built for in-tank mounting on high-performance vehicles. It undergoes the same individual flow testing to ensure it delivers the advertised performance right out of the box. This model is also engineered for complete compatibility with high-ethanol and methanol fuels, providing maximum flexibility for your fuel strategy.
The inclusion of a wiring harness, pre-filter, and O-rings means you have the essential components for a proper installation. Whether your engine requires the cooling properties of ethanol or you simply want the ultimate fuel compatibility, this pump is designed to handle it reliably. It’s a robust solution for serious performance enthusiasts who demand proven components.
QFS 340LPH E85/Flex In-Tank Performance Fuel Pump
QFS emphasizes engineering and longevity with this 340 LPH performance fuel pump. The design focuses on balancing volume, pressure, and the turbine impeller angle to prevent fuel overheating, which is a common cause of pump failure in high-performance scenarios. This careful engineering aims to provide problem-free operation for over 100,000 miles.
This pump is flow-tested to guarantee accurate performance, ensuring your upgraded engine receives the fuel it needs. It is constructed from materials capable of handling high-octane and E85 flex fuels, surpassing industry standards for durability. The package often includes a universal master install kit with strainers, filters, and hose clamps, adding significant value and simplifying the upgrade process.
Walbro 400 LPH High Flow In-Tank Fuel Pump
Walbro is a legendary name in high-performance fuel systems, and their 400 LPH pump continues that tradition of excellence. This unit offers a significant step up in flow capacity compared to 340 LPH models, making it suitable for extreme horsepower applications where maximum fuel delivery is non-negotiable. It is designed as an in-tank pump for optimal performance and noise reduction.
Built to Walbro’s stringent quality standards, this pump is known for its reliability and consistent performance under demanding conditions. While specific fuel compatibility should be verified, Walbro pumps are generally trusted for use with racing fuels and high-ethanol blends in dedicated kits. For builders who refuse to compromise on fuel supply, this 400 LPH pump is a top-tier choice from a market leader.
AEM 380 LPH High Flow In-Tank Fuel Pump
The AEM 380 LPH fuel pump sits between the standard 340 LPH and larger 400 LPH units, offering a great balance for builds that need more than a 340 but may not require a full 400 LPH. This increased flow rate provides additional headroom for future power upgrades or for engines operating at very high fuel pressures. It is designed for in-tank installation in high-performance vehicles.
As with other AEM high-flow pumps, you can expect rigorous factory testing to ensure it meets its flow specifications. This model is suited for a variety of applications, including forced induction and all-out race engines. It represents a solid middle-ground option for enthusiasts seeking robust performance and the reliability associated with the AEM brand.
DeatschWerks DW300 340 LPH In-Tank Fuel Pump
DeatschWerks has built a strong reputation for producing high-quality fuel system components, and the DW300 is a prime example. This 340 LPH in-tank fuel pump is engineered for performance and reliability, making it an excellent choice for daily-driven performance vehicles and weekend track cars alike. It is designed to be a direct drop-in replacement for many OEM applications.
The DW300 is built using a precision brushless motor and advanced materials to ensure long service life and consistent fuel delivery. It is an ideal upgrade for turbocharged or supercharged applications where the factory fuel pump is no longer sufficient. Known for its quiet operation and OEM-level fitment, the DeatschWerks pump is a popular choice for those seeking a seamless and reliable performance upgrade.
Buying Guide: How to Choose the Best 8 LPH Fuel Pump
When you’re building a high-performance engine, every component matters, and the fuel pump is the heart of your fuel system. An 8 LPH (liters per hour) pump is a solid choice for a wide range of builds, from aggressive street cars to dedicated track machines. But not all pumps are created equal. I’ve learned through trial and error that picking the right one comes down to a few key factors beyond just the flow rating.
First, you need to think about pressure. Fuel flow ratings are almost always given at a specific pressure, commonly 40 or 45 PSI for port-injected engines, and much higher for direct injection. An 8 LPH pump that flows great at 40 PSI might struggle to deliver that same volume at 60 PSI. Always check the pump’s flow chart. Your engine’s fuel pressure requirement is non-negotiable. I always match the pump’s best performance to the static pressure my fuel injectors and regulator are designed for.
Next, consider the pump technology itself. There are two main types: in-tank and inline. An in-tank pump sits inside your fuel tank, using the surrounding fuel to keep it cool and quiet. It’s my go-to for most street applications because it’s reliable and less prone to vapor lock. An inline pump, mounted in the engine bay along the fuel line, can be easier to install or replace, but it often runs louder and needs careful mounting to avoid transferring vibration. For a high-performance street car, I usually stick with a high-quality in-tank unit.
Electrical demands are another big one. High-performance fuel pumps draw more current. That stock wiring from your factory pump might not cut it. I always check the amperage draw of the new pump and upgrade the wiring with a relay and a heavier gauge wire if necessary. Running a pump on inadequate wiring is a surefire way to kill it prematurely and potentially leave you stranded. A proper voltage supply is just as important as the pump itself.
Finally, don’t forget about compatibility. Is the pump designed for use with modern ethanol-blended fuels like E85? If you plan on running flex fuel, this is a must. E85 is more corrosive and requires different seals and materials inside the pump. I make sure any pump I consider is explicitly rated for the type of fuel I’ll be using. Getting the right 8 LPH fuel pump for your high-performance engine isn’t just about a number; it’s about matching its capabilities to your engine’s specific needs for pressure, placement, power, and fuel type.
FAQ
Is an 8 LPH fuel pump enough for my turbocharged engine?
It can be, but it really depends on your engine’s horsepower goal and fuel pressure. An 8 LPH pump is a capable unit, often supporting engines in the 400-500 horsepower range with standard port injection. However, you need to do the math. Factor in your injector size, desired fuel pressure (especially under boost), and a safety margin. If you’re pushing significant boost or running high base pressure, you might be better off with a slightly larger pump to ensure you never run lean at high RPM.
What’s the difference between an in-tank and an inline 8 LPH pump?
The main difference is location and cooling. An in-tank pump is submerged in fuel, which keeps it cool and quiet. It’s generally more reliable for daily driving. An inline pump is mounted outside the tank, along the fuel line. It can be easier to access for service, but it relies on fuel flowing through it for cooling and can be noisier. For most high-performance street applications, I prefer a good in-tank setup for its durability and quiet operation.
Why is the wiring so important for a high-performance fuel pump?
High-flow pumps are power-hungry. They often draw significantly more amperage than a stock pump. Your factory wiring might be too thin, causing a voltage drop at the pump. Low voltage means the pump motor has to work harder, spins slower, and delivers less fuel and pressure. This can lead to engine damage from running lean. I always recommend installing a relay kit with thicker gauge wire directly from the battery to provide consistent, full voltage to your new pump.
Can I use any 8 LPH fuel pump with E85 fuel?
No, you cannot. You must use a pump that is specifically designed and rated for E85 compatibility. E85 (ethanol) is more corrosive than pure gasoline and can break down the internal components and seals of a pump not built for it. Using the wrong pump will lead to premature failure. Always check the manufacturer’s specifications to confirm the pump is safe for use with ethanol blends before you make a purchase for your high-performance engine.
How long does a typical high-performance fuel pump last?
There’s no single answer, as lifespan depends heavily on usage, installation quality, and maintenance. A well-installed pump in a street-driven car that isn’t constantly run at low fuel levels can last for many years, often 60,000 miles or more. Pumps in race cars that see extreme stress and heat may have a much shorter service life. The best thing you can do is always keep your fuel filter clean and avoid running the tank to empty, as this causes the pump to overheat.