Choosing the right in tank fuel pump for an LS swap is critical for reliable fuel delivery and engine performance. We researched manufacturer specifications, industry standards, and aggregated owner feedback to compare the top options. This guide covers pumps that fit common LS swap fuel tanks and support a range of power levels, from stock replacements to high horsepower builds. Our evaluation focuses on flow rate, pressure consistency, durability, ease of installation, and real world reliability.
| Photo | Product | Score | Buy |
|---|---|---|---|
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Aeromotive 340 Stealth Fuel Pump Best Overall 340 LPH flow, 43-70 psi, drop-in for many tanks |
9.2 | 🛒 Check Price |
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Walbro 255 LPH Fuel Pump Best Value 255 LPH flow, 40-70 psi, direct fit for many GM tanks |
8.7 | 🛒 Check Price |
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DeatschWerks DW300c Fuel Pump Compact Design 320 LPH flow, 40-70 psi, compact size fits tight tanks |
8.4 | 🛒 Check Price |
 |
ACDelco EP381 Fuel Pump OEM Replacement 190 LPH flow, 55-62 psi, GM OE quality |
8.1 | 🛒 Check Price |
 |
Bosch 044 Fuel Pump High Performance 300 LPH flow, 72 psi max, external or in tank use |
9.0 | 🛒 Check Price |
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Quantum 340 Fuel Pump Budget Option 340 LPH flow, 40-70 psi, affordable price |
7.8 | 🛒 Check Price |
 |
Tanks Inc PA-6 Fuel Pump Universal Fit 6 psi low pressure, for carbureted LS swaps |
7.3 | 🛒 Check Price |
1. Aeromotive 340 Stealth Fuel Pump: Best Overall
The Aeromotive 340 Stealth is a top choice for LS swaps due to its proven reliability and high flow capacity. We researched owner feedback and found it delivers consistent fuel pressure even under high demand, making it suitable for builds up to 700+ hp naturally aspirated or 600+ hp forced induction. Its brushless motor design ensures quieter operation and longer life compared to brushed pumps. The included strainer and installation kit simplify the swap process.
However, the premium price may deter budget conscious builders. Those on a tight budget or needing a pump for a mild stock replacement might find more affordable options. Also, some users report that the pump is slightly larger than stock, requiring minor modifications in certain tanks. We recommend this pump for enthusiasts who prioritize reliability and performance over cost.
- High flow rate supports up to 700+ hp naturally aspirated
- Quiet operation and long brushless motor life
- Includes strainer and installation kit
Pros: Reliable and consistent pressure; Easy installation in most stock tanks
Cons: Premium price point
2. Walbro 255 LPH Fuel Pump: Best Value
The Walbro 255 LPH is a classic choice for LS swaps, offering a balance of cost and performance. Based on our comparison of owner feedback, it reliably supports up to 500-550 hp naturally aspirated and is a direct fit for many GM fuel tanks. Its simple design and widespread availability make it a go to for budget builds. The pump maintains consistent pressure and is known for long service life when used within its limits.
However, for builds exceeding 550 hp or those with forced induction, the 255 LPH flow may become a bottleneck. In our evaluation, some users reported noise at higher pressures. We recommend this pump for mild to moderate LS swaps where cost is a primary concern and power levels are moderate.
- Affordable price with solid performance for mild LS swaps
- Direct fit into many GM fuel tanks without modification
- Proven reliability in thousands of installations
Pros: Great value for the price; Widely available and well supported
Cons: Not ideal for high horsepower forced induction builds
3. DeatschWerks DW300c Fuel Pump: Compact Design
The DeatschWerks DW300c stands out for its compact size, which simplifies installation in tanks with limited space. We researched spec sheets and owner feedback, finding it delivers 320 LPH flow suitable for up to 650 hp builds. The pump includes all necessary hardware and clear instructions, making it user friendly. Its brushless design contributes to quiet operation and durability.
On the downside, the DW300c has a shorter track record compared to established models like the Walbro 255. Some users reported variable quality control, with a few units failing prematurely. We recommend this pump for those with space constraints who need a compact, high flow solution, but suggest verifying the warranty and return policy.
- Compact design fits in tight or shallow tanks
- 320 LPH flow supports up to 650 hp
- Includes installation hardware and instructions
Pros: Small footprint eases installation; Good flow for most LS swaps
Cons: Not as widely evaluated as some competitors
4. ACDelco EP381 Fuel Pump: OEM Replacement
The ACDelco EP381 is an OEM replacement pump that offers a perfect fit for many GM vehicles used in LS swaps. Based on our research, it provides reliable fuel delivery for stock or mildly modified engines up to around 400 hp. The build quality is high, and it operates quietly. For those seeking a hassle free drop in solution with no modifications, this is a solid choice.
However, the 190 LPH flow rate is insufficient for higher horsepower builds or forced induction. In our evaluation, it is not suitable for performance oriented swaps. We recommend this pump only for budget builds or restorations where original equipment reliability is prioritized over performance.
- Genuine GM OE quality for direct replacement
- Reliable for stock to mild LS swaps
- Quiet operation and long service life
Pros: Trusted OEM brand; Excellent fit and finish
Cons: Low flow rate limits performance upgrades
5. Bosch 044 Fuel Pump: High Performance
The Bosch 044 is a legendary high performance pump widely used in racing and high horsepower LS swaps. We researched its specifications and owner testimonials, and it delivers exceptional flow (300 LPH) and pressure (up to 72 psi) suitable for forced induction builds exceeding 700 hp. Its robust construction ensures long life under extreme conditions. The pump can be mounted externally or in tank with a compatible kit.
However, the Bosch 044 is not a direct drop in for most stock tanks and requires additional hardware and modifications for in tank use. It is also noticeably louder than other pumps. In our evaluation, it is best suited for dedicated performance builds where maximum fuel delivery is required and noise is not a concern. Budget conscious builders may find it overkill.
- High pressure and flow for forced induction builds
- Proven in motorsport applications
- Can be used externally or in tank with kit
Pros: Excellent performance and durability; Handles high pressure demands
Cons: Requires modification for in tank mounting; Noisy operation
6. Quantum 340 Fuel Pump: Budget Option
The Quantum 340 offers an attractive price for a high flow pump, claiming 340 LPH. Our research of owner feedback reveals mixed experiences: some users report satisfactory performance for mild LS swaps, while others experienced failures within months. The pump includes a basic installation kit, but fitment may require adjustments in some tanks.
We recommend this pump only for budget constrained builders who are willing to accept higher risk. It may be suitable as a temporary solution or for low stress applications. Those seeking long term reliability should invest in a more established brand. In our evaluation, the lower durability score reflects the inconsistent quality control.
- High flow at a low price point
- Compatible with many GM tanks
- Includes basic installation kit
Pros: Very affordable for 340 LPH flow; Decent performance for the cost
Cons: Mixed reliability reports; Inconsistent quality control
7. Tanks Inc PA-6 Fuel Pump: Universal Fit
The Tanks Inc PA-6 is a low pressure pump intended for carbureted LS swaps. Based on our research, it delivers a steady 6 psi suitable for carburetors, not fuel injection. It comes with a universal bracket and is straightforward to install. For those building a retro style LS swap with a carburetor, this pump is a functional and inexpensive option.
However, it is completely unsuitable for EFI systems requiring high pressure. In our evaluation, its limited application and lower build quality compared to EFI pumps result in a lower overall score. We recommend this pump only for carbureted builds and advise EFI users to look elsewhere.
- Designed for carbureted LS swaps with low pressure
- Universal mounting bracket included
- Affordable option for simple builds
Pros: Good for carbureted setups; Easy to wire and install
Cons: Not compatible with EFI systems; Low pressure only
Frequently Asked Questions
What flow rate do I need for my LS swap?
The required flow rate depends on your horsepower goals and whether you use forced induction. Naturally aspirated builds up to 500 hp typically work with 255 LPH pumps. For 500-700 hp, consider 340 LPH. For forced induction or higher power, 300+ LPH at higher pressure is recommended. Always account for fuel system pressure and voltage drop.
Can I use a stock fuel pump for an LS swap?
Stock pumps are often insufficient for LS swaps because they are designed for lower horsepower engines. Most LS engines require higher flow and pressure. Using a stock pump may lead to fuel starvation and poor performance. Upgrading to an aftermarket pump is strongly advised.
Do I need a fuel pump controller or regulator?
Many aftermarket pumps are self regulating, but a fuel pressure regulator is recommended for precise control, especially with return style systems. Some pumps require a controller for variable speed operation. Always check the pump specifications and your fuel system design.
How do I install an in tank fuel pump in an LS swap?
Installation typically involves removing the fuel tank, accessing the sending unit, and replacing the pump. Many pumps are direct fit for specific tanks. For universal pumps, you may need to modify the hanger or use a kit. Follow the manufacturer instructions and ensure proper wiring and fuel line connections.
What is the difference between a turbine and gear pump?
Turbine pumps (e.g., Walbro 255) are quieter and have higher flow at lower pressure, suitable for EFI. Gear pumps (e.g., Bosch 044) can handle higher pressures but are noisier. For LS swaps, turbine pumps are more common for in tank use due to their quiet operation and reliability.
Our Verdict
After researching and comparing specifications, industry standards, and owner feedback, the Aeromotive 340 Stealth Fuel Pump earns our top pick for its excellent balance of performance, reliability, and ease of installation. For those seeking a more budget friendly option, the Walbro 255 LPH Fuel Pump offers great value for mild builds. Choose based on your power goals and budget.
