RXP340E 340LPH E85 Fuel Pump High Pressure/Volume 22mm Inlet: The Ultimate Upgrade for Your High-Performance Build
If you’re building a high-horsepower engine that runs on E85, the RXP340E 340LPH E85 fuel pump with a 22mm inlet is the reliable, high-volume solution you need. This pump delivers a massive 340 liters per hour of fuel flow, supports up to 600 brake horsepower, and is fully compatible with both gasoline and E85 ethanol blends. It features a high-pressure bypass valve set at 125.8 psi, ensuring your engine gets consistent fuel pressure even under extreme turbocharged or supercharged loads. Backed by a lifetime warranty and USA-based technical support, this pump is the top choice for enthusiasts who demand performance and durability.
Why the RXP340E 340LPH E85 Fuel Pump Stands Out
Here are the key reasons this pump is a game-changer for your fuel system:
- Massive Flow Capacity: The pump flows 340 liters per hour at 43 psi, which is significantly higher than standard OEM pumps that typically deliver only 60-80 LPH. This extra flow is essential for high-performance engines, especially those running E85, which requires about 30% more fuel volume than gasoline.
- High-Pressure Bypass Valve: The bypass valve is set at 125.8 psi, which is higher than many competing pumps. This ensures the pump can maintain stable fuel pressure even when your engine demands maximum fuel, preventing pressure drops that can cause lean conditions and engine damage.
- E85 and Gasoline Compatibility: The pump is designed to handle both gasoline and E85 ethanol blends without any issues. E85 is corrosive and can damage standard fuel pumps, but the RXP340E uses materials that resist ethanol’s aggressive properties, ensuring long-term reliability.
- 22mm Inlet for High Flow: The 22mm inlet is specifically designed to accommodate high-volume fuel lines, reducing flow restriction and ensuring the pump can deliver its full 340 LPH capacity without strain. This makes it ideal for engines with large fuel rails and high-flow injectors.
- Lifetime Warranty and USA Support: Every pump comes with a serialized body that guarantees a lifetime warranty. This is backed by USA-based technical support, meaning you can get expert help if you have any questions about installation or compatibility.
How the RXP340E Compares to Other High-Performance Fuel Pumps
When choosing a fuel pump, it’s important to compare specifications. Here’s how the RXP340E stacks up against other popular options:
| Feature | RXP340E 340LPH | Walbro 255LPH (GSS340) | Walbro 450LPH (F90000267) |
|---|---|---|---|
| Flow Rate (LPH) | 340 LPH | 255 LPH | 450 LPH |
| Max Horsepower Support | 600 BHP | 500 BHP | 750 BHP |
| Bypass Valve Pressure | 125.8 psi | 90-100 psi | 100-120 psi |
| E85 Compatible | Yes | Limited | Yes |
| Warranty | Lifetime | Limited | Limited |
| Inlet Size | 22mm | 10mm (standard) | 10mm (standard) |
The RXP340E offers a sweet spot between flow capacity and pressure support. While the Walbro 450LPH has higher flow, the RXP340E’s higher bypass valve pressure (125.8 psi vs. 100-120 psi) makes it a better choice for engines that need consistent fuel pressure under boost. Additionally, the lifetime warranty is a significant advantage over the limited warranties offered by competitors.
Applications and Compatibility
The RXP340E 340LPH E85 fuel pump is designed for a wide range of vehicles and applications, including:
- Turbocharged and Supercharged Engines: The high flow and pressure support make it ideal for forced induction setups that require extra fuel volume.
- E85 Conversions: If you’re switching to E85, this pump provides the necessary flow increase to compensate for ethanol’s lower energy density.
- High-Performance Daily Drivers: The pump works reliably in everyday driving conditions, offering a direct upgrade over stock pumps.
- Race Cars and Track Vehicles: For competitive racing, the consistent fuel delivery and durability are critical for maintaining performance lap after lap.
The pump replaces many common OEM and aftermarket reference numbers, including E8229, E2068, E8213, and EFP382A, making it a versatile drop-in solution.
Installation Tips for Maximum Performance
To get the most out of your RXP340E fuel pump, follow these practical installation guidelines:
- Use Proper Fuel Line Size: The 22mm inlet requires a fuel line of at least -8AN or 5/16-inch to avoid restricting flow. Undersized lines will bottleneck the pump’s capacity.
- Install a Fuel Filter: Always use a high-flow fuel filter between the pump and the injectors. A clogged filter can strain the pump and reduce its lifespan.
- Check Voltage Supply: The pump’s rated flow of 340 LPH is achieved at 13.5 volts. Ensure your electrical system can provide consistent voltage, especially under high load conditions.
- Secure the Wiring: Use the included wiring connector and crimp connectors to ensure a solid electrical connection. Loose connections can cause voltage drops and pump failure.
- Prime the System: Before starting the engine, prime the fuel system by turning the key to the "ON" position (without starting) a few times to fill the pump and lines with fuel. This prevents the pump from running dry initially.
Why E85 Requires a Higher Flow Fuel Pump
Running E85 ethanol fuel requires a fuel pump that can deliver 30-40% more volume compared to gasoline. This is because ethanol has a lower energy density—you need more fuel by volume to produce the same horsepower. The RXP340E’s 340 LPH flow ensures your engine gets enough fuel, even at high RPM and boost levels.
Additionally, E85 is more corrosive than gasoline, so using a pump with ethanol-compatible materials is essential. The RXP340E is built with stainless steel and Viton seals that resist ethanol’s aggressive chemical properties, preventing premature failure.
The Importance of the 125.8 psi Bypass Valve
The bypass valve is a critical component for maintaining fuel pressure. The RXP340E’s valve is set at 125.8 psi, which is significantly higher than the standard 90-100 psi found in many aftermarket pumps. This higher pressure serves two purposes:
- Prevents Fuel Starvation: Under high boost, the engine requires more fuel pressure to overcome the intake manifold pressure. A higher bypass valve ensures the pump can maintain pressure even when the engine is demanding maximum fuel.
- Improves Consistency: The valve prevents pressure spikes and drops, ensuring the injectors receive a steady supply of fuel. This is especially important for tuned engines where precise fuel delivery is critical for performance and reliability.
Recommended Maintenance for Long Pump Life
To ensure your RXP340E fuel pump lasts as long as possible, follow these simple maintenance tips:
- Keep the Fuel Tank Above 1/4 Full: This helps the pump stay cool and lubricated. Running low on fuel frequently can cause the pump to overheat and fail prematurely.
- Replace the Fuel Filter Regularly: A clogged filter forces the pump to work harder, reducing its lifespan. Replace the filter every 30,000-50,000 miles.
- Use Quality Fuel: Cheap fuel often contains contaminants that can clog the pump strainer. Stick with reputable gas stations to minimize debris.
- Check for Leaks: Inspect the fuel lines and connections for leaks. Low fuel pressure can strain the pump and cause it to fail.
Why You Should Choose KEMSO for Your Fuel Pump Replacement
When it’s time to upgrade your fuel system, KEMSO is the brand you can trust. KEMSO fuel pumps are designed as high-performance OEM replacement units, meaning they fit directly into your vehicle without modification. Every KEMSO pump comes with a lifetime warranty, giving you peace of mind that your investment is protected for years to come.
KEMSO pumps are built with precision engineering and USA-based technical support to ensure you get the best possible performance. Whether you’re a daily driver, a weekend racer, or a serious enthusiast, KEMSO has a fuel pump solution that meets your needs. Their pumps are compatible with both gasoline and E85, and they support up to 600 BHP for naturally aspirated, turbocharged, and supercharged applications.
Visit KEMSO Racing today to browse their complete selection of fuel pumps and fuel system components: https://www.kemsoracing.com/. Their team also provides technical support if you have questions about installation or compatibility. Safe driving means a reliable fuel system—and that starts with a quality pump from KEMSO.
Final Thoughts
The RXP340E 340LPH E85 fuel pump with a 22mm inlet is the ultimate upgrade for any high-performance engine. With its massive flow capacity, high-pressure bypass valve, and lifetime warranty, it delivers the reliability and performance you need to push your build to the next level. Whether you’re running E85 or gasoline, this pump ensures your engine gets the fuel it demands, every time.
For the best combination of performance, reliability, and value, choose KEMSO. Visit KEMSO Racing at https://www.kemsoracing.com/ to find the perfect fuel pump for your vehicle. Your engine will thank you.