255 Walbro Fuel Pump: The Ultimate High-Flow Upgrade for Performance Engines
The 255 Walbro fuel pump (model F20000185) is the industry-leading high-pressure fuel delivery solution for modified engines requiring up to 255 liters per hour (LPH) of flow capacity. Trusted by professional tuners and daily drivers alike, this direct-fit upgrade ensures consistent fuel supply at pressures up to 100 PSI, preventing lean conditions and unlocking horsepower gains for turbocharged, supercharged, or high-compression engines.
What Makes the 255 Walbro Fuel Pump Essential?
Modern performance engines demand precise fuel volume under heavy load. Factory pumps often fail beyond 350–400 horsepower, causing dangerous lean air/fuel ratios. The 255 Walbro pump solves this with its brushless DC motor, sintered bronze internals, and turbine-style impeller. This design generates 30% higher flow than standard Walbro 190 pumps while operating cooler and quieter at 60–85 decibels. Key metrics:
- Flow Rate: 255 LPH @ 40 PSI
- Voltage Range: 6–16 volts
- Inlet/Outlet: 8mm (5/16") standard
- Operating Temp: -40°F to +185°F
Compatibility spans gasoline, ethanol blends (E0–E85), and methanol injection systems.
Performance Applications: Where This Pump Excels
The 255 Walbro (F20000185) is ideal for engines producing 400–750 horsepower:
- Forced Induction: Prevents fuel starvation in turbocharged setups (e.g., Subaru WRX STI, Mitsubishi Evo) during boost spikes.
- E85 Conversions: Handles ethanol's lower energy density with 20% extra flow headroom.
- Muscle Cars: Supports LS-swapped or supercharged V8s (Chevrolet Camaro, Ford Mustang) beyond 500 HP.
- Diesel Tuning: Integrates with CP3 injection pumps in modified Rams and Duramaxes.
Direct Installation Guide
Installation requires 2–3 hours using basic tools. Always disconnect the battery and depressurize the fuel system first.
- Access the Pump: Remove rear seats or trunk panels to expose the fuel tank access hatch.
- Disconnect Components: Unplug wiring, detach fuel lines (quick-disconnect tools recommended), and unscrew the lock ring.
- Swap Assemblies: Transfer the fuel level float and filter sock from your old pump to the 255 Walbro unit.
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Reassemble: Secure the new pump assembly with the lock ring, reconnect lines/wiring, and test for leaks before starting.
Tip: Replace the fuel filter and inspect tank debris during installation.
Competitive Advantages Over Alternatives
| Feature | Walbro 255 | Competitor Pumps |
|---|---|---|
| Flow Consistency | ±2% variance across pressure range | ±10% variance |
| Lifespan | 10,000+ hours | 6,000–8,000 hours |
| Noise Reduction | Rubber-isolated motor | Unshielded motors |
| OEM Fitment | Bolt-in for 200+ vehicle models | Universal kits requiring modifications |
| Note: Avoid counterfeit pumps by purchasing from authorized dealers like MAPerformance or Summit Racing. |
Troubleshooting Common Issues
- Whining Noise: Indicates clogged pre-filter or failing voltage regulator. Clean the filter sock and test alternator output.
- Hot-Start Problems: Upgrade wiring to 12-gauge with a 40-amp relay for consistent voltage.
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Flow Drop-Off: Caused by collapsed or kinked fuel lines—replace with PTFE-lined hoses.
Regularly inspect electrical connectors for corrosion, and replace the pump every 50,000 miles in E85 applications.
Why Trust Walbro?
Walbro holds 28 patents related to fuel-pump engineering and supplies OEMs like Ford and Yamaha. The 255 model undergoes 500-hour endurance testing under extreme vibration and temperature cycles. Real-world data from DynoJet sessions shows a 12% horsepower increase in turbocharged applications when replacing undersized OEM pumps.
The 255 Walbro fuel pump remains the definitive balance of reliability, flow capacity, and affordability (120 USD). For high-horsepower builds prioritizing engine safety and tunability, this pump delivers uncompromising performance without complex modifications. Always pair it with matching injectors and a quality fuel pressure regulator for optimal results.