Fuel Pumps

Does your pump deliver enough fuel as boost pressure and power increase in your project? This category contains in-tank fuel pumps, inline pumps mounted in the fuel line and mechanically driven pumps. It is for you if you are upgrading your fuel supply for more power, ethanol fuel such as E85 or a new engine setup.

In-tank, inline or mechanical pump

In-tank fuel pumps sit submerged in the fuel, which cools the pump and dampens noise. Examples include the Aeromotive 525lph In-Tank Fuel Pump and the Injector Dynamics 1100lph In-Tank Brushless Fuel Pump. Inline pumps are mounted externally in the fuel line. Depending on the system, they can be used on their own or as an additional pump. Mechanical fuel pumps are driven by the engine, e.g. the belt-driven Aeromotive Atomic Belt Drive Fuel Pump.

How to choose a fuel pump

Start with your power target, then compare these factors:

• Flow at your pressure: The rated capacity typically drops as pressure rises. So compare the flow at the pressure your system runs at. This also applies under boost if the regulator raises fuel pressure.
• Fuel type: E85 typically requires more flow than petrol to make the same power, and the pump must be designed for the fuel.
• Voltage and wiring: Pump flow depends on voltage, so the relay and wire gauge can affect performance. Speed-controlled pumps such as the Aeromotive Variable Speed Controlled Fuel Pump can reduce fuel heating at low load.
• Injection or carburettor: The two systems operate at different pressures. Aeromotive Pro-Series, for example, is specified for both types.

Installation and system integration

An in-tank pump often requires a mounting kit or a complete pump module. A clean pre-filter protects the pump from dirt. Higher flow may require a pressure regulator that can handle the larger volume of fuel. Check the fuel pressure after installation, and never let the pump run dry. Besides Aeromotive, the category includes brands such as Walbro, DeatschWerks, Fuelab and Industrial Injection.

Frequently asked questions

Should I choose an in-tank pump or an inline pump?

An in-tank pump is cooled by the fuel and is typically quieter. An inline pump is mounted externally and can be easier to access. The choice depends on the tank design, the available space and whether you want to supplement an existing pump.

How do I know if the pump can be used with E85?

Check the product description for the specific part number. Some pumps are specified as E85 compatible, e.g. the Cobb High Flow E85 Capable Fuel Pump. Also remember that E85 typically requires more flow than petrol.

Should the pressure regulator be replaced together with the pump?

It depends on the system. A pump with significantly more flow can exceed what the original regulator can handle, making the pressure too high or unstable. Measure the fuel pressure after installation to be sure.

Why can a new pump cause low fuel pressure?

Typical causes are low voltage at the pump, wires that are too thin, a clogged pre-filter, a leaking connection in the tank or a regulator that does not suit the system. Check these points before replacing the pump again.