Fuel Pressure Requirements For Fitech Efi Systems

The fuel pressure for a FiTech EFI system is recommended to be at 58 lbs. However, some users have reported issues with maintaining this pressure, which can lead to lean conditions at idle. It is important to ensure that the fuel pressure gauge is accurate and that the system is installed correctly, as minor issues can have a significant impact on performance.

Fuel delivery and regulators

The recommended fuel pressure for the Fitech EFI system is 58 lbs, as mentioned by a user in the Fitech EFI Tuning Forum. However, the user also noted that they were experiencing idle issues and lean conditions with their setup, even with the recommended fuel pressure. This issue may be related to other factors in the fuel system or engine configuration.

To ensure proper fuel delivery, Fitech offers a range of fuel pumps, pressure regulators, and accessories. Their fuel delivery kits, such as the FiTech Fuel Delivery Kit 50001, provide a comprehensive solution for EFI in-line pump systems. This kit includes a 67 gph/255 lph fuel pump, 40 ft of hose, and other necessary components for a complete installation. Fitech also offers in-tank fuel pump modules, such as the Go Fuel In-Tank Pump Module 50015, which provides a 90 gph pump with a 15-amp draw and -6AN ORB inlet/outlet.

In addition to fuel pumps, Fitech offers a selection of fuel pressure regulators to maintain the correct fuel pressure. The Go Fuel Pressure Regulators, such as the 54001 model, feature a pressure gauge and -6 fittings for precise adjustment. Fitech also provides returnless fuel filters, such as the 55012 model, which combines a fuel pressure regulator with a 5-micron filter to ensure clean and properly pressurised fuel.

It is important to note that fuel delivery and regulator selection may vary depending on the specific engine configuration, fuel system setup, and performance requirements. Proper installation and maintenance are crucial to ensuring optimal fuel pressure and engine performance with the Fitech EFI system.

Minimum fuel pressure

The minimum fuel pressure for the FiTech EFI is 58 lbs. A user on the FiTech EFI Tuning Forum reported that they were getting approximately 54 lbs at idle and asked if this was causing a lean condition at idle. The user also reported high AFR readings and stated that they did not think they had an exhaust leak.

Another user on the forum suggested that the original poster try a different pressure gauge, as their experience with a stealth pump was that it would max out the pressure gauge. The original poster replied that the gauge was brand new and that they had a return line.

The issue was never resolved in the thread, but one user suggested that the problem could be due to an installation issue or something external. The user asked a series of questions to help diagnose the problem, including whether the orange (fuel pump) wire was run directly to the pump with no relay, how the pump was grounded, how the fuel lines were hooked to the FiTech, and whether the return line was hooked to the correct port.

It is important to note that fuel pressure is just one factor that can affect engine performance. Other factors include the condition of the fuel pump, fuel filters, fuel injectors, and the engine's overall health. It is always recommended to consult a professional or a mechanic when dealing with fuel systems and engine performance issues.

Fuel pressure gauge accuracy

Fuel pressure gauges are used to measure the pressure of the gasoline delivered to the engine, usually in pounds per square inch (psi). For engines with fuel injection, the pressure is often between zero and 100 psi.

There are two main types of fuel pressure gauges: mechanical and electronic. Mechanical gauges are typically plumbed into the fuel line, often directly before the carburetor. They use a valve to detect the pressure of the gasoline as it is pumped into the engine. There are two varieties of mechanical gauges: wet and dry. A wet gauge uses a dial filled with clear oil, such as glycerin, to dampen the effects of the needle's movements and prevent damage to the delicate parts. However, as the engine bay warms up, the oil temperature can affect the reading. To mitigate this, some manufacturers provide a relief valve to equalize the pressure within the indicator. Dry gauges lack this fluid, potentially making them more accurate, but they are also more susceptible to engine vibrations and may not last as long.

On the other hand, electronic gauges use a sensor in the fuel line to measure pressure and display the measurement as a number or via a needle. They provide more precise readings and have fewer moving parts, making them more durable.

When it comes to the accuracy of fuel pressure gauges, it is important to note that different engines have different fuel pressure requirements. For example, a forum user with a FiTech EFI system mentions that their system runs on 58 lbs of fuel pressure, but they are only getting approximately 54 lbs at idle, which may be causing a lean condition. This highlights the importance of having an accurate fuel pressure gauge to ensure that the engine is receiving the correct amount of fuel.

In addition to accuracy, it is also crucial to consider the safety implications of installing a fuel pressure gauge. While mechanical gauges are typically installed near the fuel line in the engine bay, it is not safe to have a fuel line inside the passenger compartment. Therefore, if you want to access the fuel pressure reading while driving, you may want to consider an electronic gauge, which can be placed anywhere, even on the dashboard, as the signal is sent via wires.

Fuel pump wiring

Wiring Basics

The Fitech EFI system features an ECM (Electronic Control Module) that controls the fuel pump using Pulse Width Modulation (PWM). This allows the ECM to adjust the fuel pump's output to meet the engine's fuel demands. The ECM connects to the fuel pump via a thin 16-gauge orange wire.

Wire Gauge and Length Considerations

It is important to ensure that the wiring can handle the amperage requirements of the fuel pump over the length of the circuit. For longer wiring runs, consider upgrading to a larger wire gauge, such as 10-gauge wire, to prevent voltage drops and ensure adequate power delivery to the pump.

Relay Usage

Some installers choose to add a relay to the fuel pump circuit to reduce the power load on the orange wire. This involves connecting the orange wire to the low-power side of the relay (typically pins 85 and 86). However, doing so will result in the loss of PWM control, and the pump will need to be set to run at 100%bypass the orange wire and run a larger gauge wire directly from the junction bar to the pump. This approach ensures that the pump receives sufficient power but will void the Fitech warranty.

Fuse Protection

It is recommended to install a fuse near the pump to provide added protection. A 15-amp fuse is the maximum recommended by Fitech to safeguard the system without compromising performance.

Troubleshooting Fuel Pressure

If you are experiencing issues with fuel pressure, there are several factors to consider. Ensure that the return line is connected to the correct port, typically on the back passenger side of the vehicle. Check that the pump is receiving adequate power and is properly grounded. A faulty fuel pressure gauge could also be the culprit, so testing with a different gauge may be advisable.

In summary, fuel pump wiring for the Fitech EFI system involves considerations such as wire gauge, relay usage, direct wiring, fuse protection, and troubleshooting fuel pressure issues. By following these guidelines and tailoring the wiring setup to your specific needs, you can ensure reliable fuel delivery and optimal performance from your Fitech EFI system.

Fuel line hookup

The FiTech EFI system is a self-tuning fuel injection system that can support up to 400-650 horsepower. It simplifies the switch from a carburetor to an EFI system, with no adjustments required to the ignition. The system includes a fuel pump, a fuel pressure regulator, and a throttle body, among other components.

The fuel line hookup for the FiTech EFI system involves connecting the fuel lines between the fuel tank and the engine. The process is as follows:

First, measure the length of fuel line required, taking into account any bends or routing specific to your vehicle. The fuel line will run from the fuel tank to the engine, where the FiTech EFI system is located. It is recommended to use EFI-grade fuel hose for both the inlet and return lines. The hose should be AN6 size, which is commonly used for EFI installations. The length of the hose will depend on the specific vehicle and engine configuration.

Next, you will need to select the appropriate fuel pump for your application. The WALBRO 255L fuel pump is a popular choice for EFI systems and can be used as either an in-tank or in-line pump. If you choose an in-tank pump, ensure compatibility with your sending unit. The pump should be connected directly to the orange wire of the FiTech EFI system, without a relay.

Then, adapt the fuel lines to the correct size. Fuel cells typically use AN bulkhead fittings, which may require AN-to-AN6 adapter fittings. Fuel tank sending units may use tube-to-AN adapters if they were previously set up for rubber lines and hose clamps. It is important to ensure compatibility between the sending unit and the fuel lines.

Finally, connect the fuel lines to the FiTech EFI system. The inlet and return lines should be clearly marked on the system. The return line should be connected to the correct port, which is typically located on the back passenger side of the vehicle when facing forward.

It is important to note that the FiTech EFI system operates at a higher fuel pressure compared to a carbureted system. The recommended fuel pressure for the FiTech EFI system is 58 psi. However, some users have reported issues with achieving this pressure, and it may be necessary to adjust the PWM setting or consult with a professional for further troubleshooting.

Frequently asked questions