Best Subaru Upgrade Fuel Pumps for Enhanced Performance

When I first started dabbling with modifying my Subaru, one of the most common bottlenecks I encountered, especially when chasing more horsepower, was the fuel system. It’s a classic scenario: you upgrade your turbo, injectors, or get a more aggressive tune, and suddenly, your stock fuel pump just can’t keep up. That’s when I realized the critical importance of having a robust fuel pump – it’s the heart of your car’s performance. Choosing the best Subaru upgrade fuel pump for enhanced performance isn’t just about throwing the highest flow rate pump at it; it’s about finding the right balance of reliability, compatibility, and the flow rate needed for your specific power goals. In this guide, I’ll walk you through some of the top contenders in the market, sharing my insights and helping you make an informed decision for your beloved Subaru, whether you’re building a monster or just looking for rock-solid reliability.

IMAGE	PRODUCT NAME	AMAZON LINK
	KEMSO 340LPH High Performance Fuel Pump, Replaces Walbro…	View on Amazon
	KEMSO 340LPH High Performance Fuel Pump for Subaru/Honda…	View on Amazon
	KEMSO 340LPH High Performance Fuel Pump for Subaru Legacy…	View on Amazon
	Electric Fuel Pump Assembly FIT Subaru Impreza 2008–2011,…	View on Amazon
	QFS-344FT-1008 Performance Fuel Pump & Install Kit 340lLPH…	View on Amazon
	KEMSO 340LPH High Performance Fuel Pump for Subaru/Honda…	View on Amazon
	TRQ Fuel Pump Module Assembly Compatible with 2008-2010…	View on Amazon

KEMSO 340LPH High Performance Fuel Pump, Replaces Walbro…

This KEMSO 340LPH pump is often seen as a direct competitor or alternative to popular aftermarket options like Walbro, offering similar performance characteristics at a competitive price. It’s designed to provide a significant boost in fuel delivery, supporting a wide range of power outputs for naturally aspirated, turbocharged, or supercharged Subaru builds. What I really appreciate is their USA-based support, which can be a lifesaver if you run into any installation or performance questions. Plus, knowing it’s designed for both gasoline and E85 compatibility gives you excellent flexibility for future tuning goals. This pump truly aims to be a reliable workhorse for those pushing their engines.

Key features:
– Supports up to 600 BHP in N/A, Turbocharged, and Supercharged applications.
– Kemso Support for our pumps is USA based and provided by USA technicians.
– Designed for gasoline or E85.
– Bypass valve set at 125.8psi, higher than both GSS series 255LPH pumps, and 400/ 450LPH pumps.
– Serialized fuel pump body guarantees Lifetime warranty.

Pros:
– High flow rate suitable for serious power gains.
– E85 compatible, offering tuning flexibility.
– Excellent lifetime warranty from a reputable company.
– USA-based technical support is a huge plus.

Cons:
– Installation might require some mechanical aptitude.
– Can be slightly noisier than stock pumps, though typical for performance units.

Best for: Enthusiasts running significant power upgrades (up to 600hp) who need an E85-compatible, reliable fuel pump with strong warranty support.

User feedback summary: Many users praised its easy installation into various Subaru models, noting an immediate improvement in fuel delivery and the ability to hold higher boost pressures without fuel cut. The lifetime warranty also provides significant peace of mind. Some mentioned a slight hum but consider it acceptable for a performance pump.

KEMSO 340LPH High Performance Fuel Pump for Subaru/Honda…

Another strong offering from KEMSO, this 340LPH pump specifically targets Subaru and Honda owners looking for a performance upgrade. Much like its sibling above, it provides the essential flow rate needed to support higher horsepower applications, making it a go-to for many tuners and DIY enthusiasts. The focus here is on broad compatibility within performance-oriented Japanese vehicles, ensuring that a wide range of popular builds can benefit. With the same robust design and commitment to quality, including E85 compatibility and a lifetime warranty, it’s a solid choice if you’re upgrading your fuel system for increased power.

Key features:
– Supports up to 600 BHP in N/A, Turbocharged, and Supercharged applications.
– Kemso Support for our pumps is USA based and provided by USA technicians.
– Designed for gasoline or E85.
– Bypass valve set at 125.8psi, higher than both GSS series 255LPH pumps, and 400/ 450LPH pumps.
– Serialized fuel pump body guarantees Lifetime warranty.

Pros:
– Ideal for high-horsepower Subaru and Honda builds.
– E85 friendly for advanced tuning.
– Backed by a lifetime warranty and USA support.
– Reliable fuel delivery for demanding applications.

Cons:
– May require slight modifications for perfect fitment in some specific models.
– Performance pumps often have a noticeable whine compared to OEM.

Best for: Subaru and Honda enthusiasts pushing their engines to 600 BHP, seeking a durable and flexible fuel pump solution.

User feedback summary: Owners frequently highlight its excellent flow and pressure, stating it’s a reliable upgrade for tuned vehicles. The inclusion of a lifetime warranty and responsive US customer service were standout features for many, making the investment feel secure.

KEMSO 340LPH High Performance Fuel Pump for Subaru Legacy…

For Subaru Legacy owners who are looking to upgrade their fuel system, this specific KEMSO 340LPH pump is tailored to meet those needs. While sharing the same high-performance specifications as other KEMSO 340LPH units, this one is often marketed with specific attention to Legacy fitment, which can ease concerns about compatibility. It’s an ideal choice for boosting your Legacy’s power output, ensuring a consistent and ample fuel supply whether you’re adding a turbo, larger injectors, or simply getting a custom tune. The peace of mind offered by the lifetime warranty and USA-based support remains a significant advantage for any performance enthusiast.

Key features:
– Supports up to 600 BHP in N/A, Turbocharged, and Supercharged applications.
– Kemso Support for our pumps is USA based and provided by USA technicians.
– Designed for gasoline or E85.
– Bypass valve set at 125.8psi, higher than both GSS series 255LPH pumps, and 400/ 450LPH pumps.
– Serialized fuel pump body guarantees Lifetime warranty.

Pros:
– Strong performance for Subaru Legacy models.
– E85 compatibility opens up more tuning possibilities.
– Comes with a comprehensive lifetime warranty.
– US-based technical support is readily available.

Cons:
– Not a plug-and-play solution for all Legacy sub-models without some adjustment.
– Can be slightly louder than the stock pump.

Best for: Subaru Legacy owners aiming for high horsepower figures and needing a reliable, E85-compatible fuel pump with solid customer support.

User feedback summary: Legacy owners specifically noted its improved fuel delivery, eliminating lean conditions experienced with stock pumps under hard acceleration. The direct fitment for many Legacy models was a plus, and the reliability for both daily driving and spirited use was consistently praised.

Electric Fuel Pump Assembly FIT Subaru Impreza 2008–2011,…

Unlike the pure performance-oriented pumps, this Electric Fuel Pump Assembly is designed as a direct OEM replacement, focusing on restoring your Subaru’s original fuel system performance. If your Impreza, Legacy, or Outback is experiencing sputtering, hard starts, or reduced fuel efficiency due to a failing pump, this assembly is built to get you back on track. It matches OEM flow rates and pressure output, ensuring your car runs as it should. The fact that it’s pre-assembled for drop-in installation means you won’t have to deal with cutting or splicing wires, making the repair much more straightforward for the average DIYer.

Key features:
– Vehicle Fitment: Fits 2008-2011 Subaru Impreza 2.5L H4, 2006-2009 Subaru Legacy 2.5L H4, 2006-2009 Subaru Outback 2.5L H4.
– Replaces OE part numbers: E8651M, P76427M, ensuring OEM compatibility.
– Engineered to match OEM connector, flow rate, and pressure output.
– Built with ethanol-resistant components, sealed electric pump motor, and integrated float sensor.
– Pre-assembled for drop-in installation with no cutting or splicing.

Pros:
– Direct OEM fit and function for specific Subaru models.
– Easy drop-in installation, no modifications needed.
– Restores original fuel system pressure and smooth idle.
– Ethanol-resistant components for modern fuels.

Cons:
– Not designed for significant performance upgrades beyond stock.
– Specific vehicle fitment means checking compatibility is crucial.

Best for: Subaru Impreza, Legacy, or Outback owners (specific years/engine) looking to replace a failing stock fuel pump with an OEM-spec, easy-to-install unit to restore original performance.

User feedback summary: Many appreciated the true plug-and-play nature of this assembly, saving them time and effort. Users reported immediate fixes to fuel delivery issues and smooth engine operation. The quality was often compared favorably to the original part, and the price point was seen as very reasonable.

QFS-344FT-1008 Performance Fuel Pump & Install Kit 340lLPH…

Quantum Fuel Systems (QFS) offers this 340LPH performance fuel pump as a robust solution for upgrading your Subaru’s fuel system. Similar to the KEMSO units, it’s designed to support high horsepower applications up to 600 BHP, making it a serious contender for modified Subarus. What stands out is QFS’s dedication to reliability and longevity, coupled with their in-house customer service team based in the USA. This pump also boasts E85 compatibility, giving you the flexibility to run alternative fuels for even greater performance. It comes as a kit, which often means you get the necessary installation components, simplifying the upgrade process.

Key features:
– Supports Up To 600 Bhp In N/A, Turbocharged, And Supercharged Applications.
– Designed For Gasoline Or E85.
– The ultimate in peak engineering to guarantee reliability and longevity.
– Lifetime Warranty With Dedicated In-House Customer Service Team In The Usa Based In Ventura, California.

Pros:
– High flow rate for substantial power gains.
– E85 compatible for performance tuning flexibility.
– Lifetime warranty and dedicated USA customer service team.
– Focus on reliability and longevity.

Cons:
– May require professional installation for optimal performance and tuning.
– Can produce a noticeable sound when operating, typical for high-flow pumps.

Best for: Performance enthusiasts needing a reliable 340LPH pump for up to 600 BHP, especially those who value a strong USA-based support team and a lifetime warranty.

User feedback summary: Users often noted its powerful and consistent fuel delivery, supporting aggressive tunes without issues. The comprehensive install kit was a big plus, and the peace of mind from the lifetime warranty and accessible customer service was frequently mentioned.

KEMSO 340LPH High Performance Fuel Pump for Subaru/Honda…

This is another listing for the highly capable KEMSO 340LPH performance fuel pump, reinforcing its widespread availability and popularity among Subaru and Honda enthusiasts. It’s essentially the same powerful unit as KEMSO 2, offering the same impressive 600 BHP support and E85 compatibility that tuners crave. The consistency across these KEMSO listings speaks to the brand’s confidence in this particular model. If you’re searching for a reliable, high-flow pump with excellent backing from USA-based technical support and a lifetime warranty, this KEMSO unit continues to be a top recommendation for enhancing your Subaru’s performance.

Key features:
– Supports up to 600 BHP in N/A, Turbocharged, and Supercharged applications.
– Kemso Support for our pumps is USA based and provided by USA technicians.
– Designed for gasoline or E85.
– Bypass valve set at 125.8psi, higher than both GSS series 255LPH pumps, and 400/ 450LPH pumps.
– Serialized fuel pump body guarantees Lifetime warranty.

Pros:
– Proven performance for high-horsepower builds.
– E85 compatibility provides flexibility for tuning.
– Lifetime warranty offers long-term security.
– USA-based support for installation or troubleshooting.

Cons:
– Installation can be challenging for beginners.
– May exhibit typical performance pump noise.

Best for: Subaru and Honda owners aiming for significant power increases, looking for a reliable and warrantied fuel pump that can handle E85.

User feedback summary: Consistent with other KEMSO 340LPH pumps, users reported excellent flow and pressure, solving fuel delivery issues in highly modified vehicles. The lifetime warranty was a recurring highlight, providing confidence in its longevity. Installation was straightforward for those with some mechanical experience.

TRQ Fuel Pump Module Assembly Compatible with 2008-2010…

The TRQ Fuel Pump Module Assembly provides a reliable and cost-effective solution for replacing a faulty fuel pump in specific Subaru models. It’s designed to be a direct fit replacement, ensuring that your vehicle’s fuel system is restored to its original operating specifications without the need for complex modifications. While it doesn’t offer the high-flow rates of performance pumps, it’s perfect for those who need to fix an existing problem and maintain stock reliability. The 2-year/24,000-mile warranty gives you some assurance for the product’s quality, making it a practical choice for everyday drivers.

Key features:
– TRQ products are covered by a 2-year / 24,000-mile warranty.
– Reference Number(s): E9054M, ensures direct OEM compatibility.
– Electrical Connector Quantity: 1, simplifying installation.
– Designed for specific 2008-2010 Subaru Impreza, Legacy, and Outback models.

Pros:
– Direct OEM replacement for easy installation.
– Cost-effective solution for restoring stock fuel system performance.
– Comes with a 2-year/24,000-mile warranty.
– Addresses common fuel pump failure symptoms.

Cons:
– Limited to OEM performance, not suitable for high-horsepower upgrades.
– Warranty period is shorter compared to some performance brands.

Best for: Subaru Impreza, Legacy, and Outback owners (specific years) who need a reliable, budget-friendly replacement for a failing OEM fuel pump, prioritizing stock performance and easy installation.

User feedback summary: Owners found this TRQ assembly to be an accurate fit and a straightforward replacement for their original units. Many reported it resolved issues like hard starting and engine stalls. The value for money was frequently mentioned, especially when compared to dealership prices for OEM parts.

Helpful Comparison Insights

When you’re looking for the best Subaru upgrade fuel pump for enhanced performance, it’s crucial to understand the two main categories we’ve covered: pure performance upgrades and OEM-style replacements.

For those chasing horsepower, the KEMSO 340LPH and QFS 340LPH pumps are your go-to options. They all offer a high flow rate of 340 liters per hour (LPH), which is significantly more than stock, capable of supporting up to 600 BHP. This means they can feed larger injectors and higher boost pressures without causing lean conditions. A major advantage across these performance pumps is their E85 compatibility, allowing you to run ethanol-based fuels which offer higher octane and cooling properties for more aggressive tuning. KEMSO and QFS both provide a lifetime warranty and commendable USA-based customer support, which really adds value and confidence to your purchase. The main difference between the KEMSO listings (1, 2, 3, 6) often boils down to specific vehicle fitment marketing, but the core pump’s performance characteristics remain consistent. While these pumps are powerful, they might require some minor modifications for installation in some specific Subaru models and often produce a slight whine audible in the cabin, which is common for higher-flow pumps.

On the other hand, if your goal is to simply restore your Subaru’s original performance and reliability due to a failing pump, the Electric Fuel Pump Assembly (Product 4) and the TRQ Fuel Pump Module Assembly (Product 7) are excellent choices. These are direct OEM replacements, engineered to match stock flow rates and pressure. Their biggest benefits are ease of installation – often pre-assembled for a true drop-in fit with no cutting or splicing – and their ability to bring your car back to factory-spec operation. They are not designed for performance upgrades beyond stock, so don’t expect them to support big turbos or E85 tunes. The TRQ pump offers a 2-year/24,000-mile warranty, while the Electric Fuel Pump Assembly focuses heavily on matching OEM specs and durability with ethanol-resistant components. Choosing between these depends on your specific model year compatibility and preferred warranty coverage.

In summary, if you’re building a fast Subaru, opt for a 340LPH performance pump like KEMSO or QFS for increased fuel delivery and E85 capability. If your Subaru is struggling and you just want it running reliably like it used to, an OEM-style replacement from TRQ or the generic Electric Fuel Pump Assembly will be a simpler, more direct solution.

Final Verdict

Deciding on the best Subaru upgrade fuel pump for enhanced performance truly hinges on your individual goals and the current state of your vehicle.

If your Subaru is destined for the track, the drag strip, or just a spirited daily drive with serious power modifications, you absolutely need a high-flow pump. For these scenarios, the KEMSO 340LPH and QFS 340LPH units are top-tier choices. They offer the flow, the E85 compatibility, and the peace of mind of a lifetime warranty. My personal leaning would be towards the KEMSO 340LPH pumps (like the ones listed as 1, 2, 3, or 6) due to their consistent positive feedback, strong US-based support, and their proven track record in supporting substantial horsepower gains without skipping a beat. The QFS 340LPH (Product 5) is also an incredibly strong contender, offering very similar benefits and an excellent support system. For those pushing 400-600 BHP, either of these brands will serve you well.

However, if your Subaru is experiencing the classic symptoms of a dying fuel pump – struggling to start, sputtering, or general hesitation – and you simply want to restore it to its original, reliable glory without diving into performance tuning, then the OEM-style replacement options are your best bet. The Electric Fuel Pump Assembly (Product 4) is fantastic for specific Impreza, Legacy, and Outback models, providing an easy, direct-fit solution to get your car running smoothly again. Similarly, the TRQ Fuel Pump Module Assembly (Product 7) is another solid choice for specific model years, offering a reliable fix with a decent warranty. These pumps won’t add horsepower, but they will ensure your existing setup runs optimally, which is a form of enhanced performance in itself!

Ultimately, for serious power, go with a 340LPH performance pump. For reliable stock replacement, choose an OEM-style module that fits your specific model.

Comprehensive FAQ Section

Q1: Why do I need an upgrade fuel pump for my Subaru?
A: You’ll typically need an upgrade fuel pump if you’ve modified your Subaru for more power, such as installing a larger turbo, bigger injectors, or getting an aggressive tune. The stock fuel pump often can’t deliver enough fuel to support these modifications, leading to dangerous lean conditions and potential engine damage. An upgrade fuel pump ensures adequate fuel delivery for your enhanced performance needs.

Q2: What does “LPH” mean, and how much do I need?
A: LPH stands for “Liters Per Hour” and indicates the flow rate of the fuel pump. For lightly modified Subarus (e.g., stage 1/2 tunes), the stock pump might be sufficient. However, for significant power upgrades (e.g., 400+ horsepower), a 340 LPH fuel pump is a common and recommended upgrade to ensure your engine receives enough fuel.

Q3: Is E85 compatibility important for a Subaru upgrade fuel pump?
A: Yes, very much so for performance builds! E85 (ethanol fuel) has a higher octane rating and provides better cooling properties than gasoline, allowing for more aggressive tuning and often more horsepower. However, E85 is corrosive to non-compatible fuel system components, so an E85-compatible fuel pump (like the KEMSO and QFS 340LPH pumps) is crucial if you plan to run it.

Q4: Can I install an upgrade fuel pump myself, or should I get a professional?
A: Installing an upgrade fuel pump often involves removing the rear seats, accessing the fuel tank, and handling fuel lines. While many DIY enthusiasts do it, it requires some mechanical skill and an understanding of safety precautions when working with fuel. For performance pumps, a professional installation is often recommended, especially since a proper tune is usually required afterward to take advantage of the increased fuel flow. OEM replacement pumps (like TRQ or Electric Fuel Pump Assembly) are typically more straightforward “drop-in” installations.

Q5: What are the signs that my Subaru’s fuel pump is failing?
A: Common signs of a failing fuel pump include difficulty starting your car (cranking but not turning over easily), a whining noise coming from the fuel tank, engine sputtering or stalling (especially at high speeds or under acceleration), noticeable loss of power, and decreased fuel efficiency. Addressing these symptoms promptly with a Subaru upgrade fuel pump for enhanced performance or a reliable OEM replacement is important.

Q6: Do I need to get my car tuned after installing an upgrade fuel pump?
A: Absolutely, yes! If you install a higher-flow performance fuel pump, you must get a professional tune. Without a proper tune, your engine’s computer will still be programmed for the stock fuel pump’s flow rate, which can lead to your engine running extremely rich (too much fuel) or, worse, inconsistent fuel pressure that could still cause lean spots. A custom tune ensures your engine properly utilizes the new pump and runs safely.

Q7: How does a fuel pump contribute to “enhanced performance”?
A: A fuel pump directly contributes to enhanced performance by ensuring your engine receives a consistent and adequate supply of fuel, especially under high-demand conditions (like acceleration or boosting). For performance upgrades, a stronger pump prevents fuel starvation, allowing your engine to safely produce more power with larger turbos, injectors, or aggressive tunes. For OEM replacements, it enhances performance by restoring the car’s original reliable operation, eliminating power loss or sputtering caused by a failing pump.