Walbro High-Flow Fuel Pumps

What are the best high-flow fuel pumps for a modified Subaru WRX or STI? For most bolt-on builds, the Walbro 255LPH pump is the proven answer — it supports roughly 400 horsepower on gasoline. When you step up to E85 or serious power, the 450LPH E85 version moves far more volume and is built to withstand ethanol. This collection gathers JDMuscle's full Walbro fuel pump lineup, from vehicle-specific kits to universal pumps.

What High-Flow Fuel Pumps Do

A fuel pump feeds fuel from the tank to the engine at the pressure your regulator demands. The stock pump is sized for stock power; once you add a bigger turbo, larger injectors, or switch to E85 — which needs roughly 30 percent more fuel volume for the same power — the factory pump can run out of flow and let the engine run lean under boost. Compare the flow rating in liters per hour, confirm ethanol compatibility for flex fuel, and choose between a pump-only unit and a complete install kit. Check your year and model before ordering.

About Walbro

Walbro is the name most tuners reach for first when fueling gets serious, and that reputation comes from decades of OE-level fuel system engineering — the company has long supplied fuel components to major automakers, so its aftermarket pumps inherit genuine fuel-system expertise. The 255LPH pump became the default upgrade for a generation of turbo Subarus, delivering a large flow increase while staying quiet and reliable enough for daily driving. Walbro kept pace with the market: the 450LPH and 525LPH pumps brought real headroom to high-horsepower and E85 builds, including ethanol-rated versions like the F90000267 in this collection.

Completing Your Fuel System

A pump rarely works alone. Aeromotive is a natural companion brand — its regulators, rails, and pumps share the same high-flow philosophy. DeatschWerks covers the other end of the system with injectors and drop-in pumps, so pump and injector upgrades can be sized as a matched pair.

Popular picks include the Walbro 255LPH Fuel Pump + Kit for 02-07 WRX and 04-07 STI, the 450LPH E85 Fuel Pump and Installation Kit, and the 450LPH High Pressure In-Tank Pump. Browse the full fuel system collection, add a fuel pressure regulator if yours is original, and read our guide to Subaru engine modifications.

Frequently Asked Questions

Do I need to upgrade my fuel pump for bolt-on mods?

A Stage 2 WRX (intake, downpipe, tune) can run on the stock pump, but it is near its limit. The 255LPH is inexpensive insurance and becomes required with a bigger turbo, larger injectors, or E85.

Do I need a tune after installing a fuel pump?

No — a pump swap alone does not change fuel delivery, since the regulator controls pressure. But if you also change injectors or fuel type, the car needs a tune immediately.

Can I run E85 with a standard Walbro 255LPH?

The standard pump is not rated for long-term ethanol exposure. Choose an E85-rated version like the 450LPH F90000267 in this collection, with ethanol-ready lines, injectors, and tune.

How hard is the install?

On most Subarus it is a one-to-two-hour job through the tank access panel, and vehicle-specific kits include the strainer and wiring. Universal pumps may need hanger modification — check your year and model first.