TI Automotive (Walbro) 180LPH External EFI Fuel Pump (GSL394)

Reliable High-Flow Fuel Delivery for Performance Applications

The TI Automotive (Walbro) GSL394 (Cross Reference – EFP-637) is an externally mounted fuel pump designed to deliver a steady, dependable fuel supply across a wide range of performance vehicles. Flowing 180 LPH @ 40 psi, it's built to comfortably support applications in the 300–350 horsepower range, making it a solid upgrade for street and mild performance builds running on petrol.

Fitted with interchangeable inlet and outlet fittings, this fuel pump delivers:

• Steady, dependable fuel supply – supports efficient engine performance
• Interchangeable inlet & outlet fittings – adapts to your existing fuel line setup
• Internal check valve – maintains system pressure and improves hot-start reliability

Flow Chart & Pump Diagram

GSL394 Dimensional Drawing (PDF)

Technical Specifications

• Common Names / Cross Reference: Walbro GSL394, EFP-637
• Flow Rate: 180 LPH @ 40 psi (155–190 LPH range)
• Fuel Type: Petrol (Gas)
• Horsepower Support: 300–350 HP
• Max Pressure: 87 psi
• Internal Check Valve: Yes
• Pump Body Size: 43mm
• Mounting Type: Externally Mounted (In-Line)

Includes fitting kit: Interchangeable inlet and outlet fittings. Pair with a quality external fuel filter for a complete install.