Adjusting Fuel Pressure Regulators: Summit Guide

Summit Racing offers a wide range of fuel pressure regulators for different engines, including carbureted and fuel-injected applications. Their 4-port fuel pressure regulators are crafted from billet aluminum and anodized for a sleek look under the hood. These regulators are designed to boost engine performance and are easy to install and adjust for fine-tuning. With a linear rising rate of 1:1 up to 20 PSI of boost, they offer precise control over fuel pressure. Summit Racing also provides a variety of other fuel pressure regulators with different pressure ranges, styles, and capacities to suit diverse engine requirements.

Summit Racing 4-Port Fuel Pressure Regulators

The Summit Racing 4-Port Fuel Pressure Regulators are designed to feed your power-hungry engine for maximum performance. They are crafted from billet aluminum and are anodized, offering a great look under your hood to match their performance. The regulators have a linear rising rate of 1:1 up to 20 PSI of boost, then a rate of 0.75:1 once 20 PSI is exceeded. They are easy to install and adjust, allowing you to fine-tune and dial in your performance.

These regulators are suitable for carbureted or EFI applications and can be used with stock or mildly modified pump gas engines, as well as high-performance race engines. The Summit Racing 4-Port Fuel Pressure Regulators have a pressure range of 1.5-25 psi and feature a return style, inline design. The regulator inlet and outlet sizes are female straight cut O-rings, and a mounting bracket is included.

To adjust the Summit Racing 4-Port Fuel Pressure Regulators, you can follow these general steps:

• Consult the instruction manual provided with the regulator for specific instructions and safety precautions.
• Locate the regulator in your engine bay. It should be installed inline with the fuel lines, between the fuel pump and the injectors.
• Identify the adjustment screw or knob on the regulator. This is typically a small screw or knob located on the top or side of the regulator.
• Using a small screwdriver or wrench, turn the adjustment screw or knob clockwise to increase the fuel pressure or counterclockwise to decrease the fuel pressure. Make adjustments in small increments to avoid over-tightening or under-tightening the screw.
• After each adjustment, start the engine and check the fuel pressure gauge to ensure the desired pressure has been achieved.
• Once the desired fuel pressure is reached, test the vehicle to ensure proper engine performance and confirm that there are no leaks in the fuel system.
• If you are satisfied with the performance and there are no leaks, tighten any locking nuts or screws on the adjustment mechanism to secure the setting.

Note: It is important to adjust the fuel pressure regulator with caution and in small increments to avoid damaging the engine or fuel system. Always refer to the manufacturer's instructions and recommendations for specific adjustment procedures and settings.

Installation and adjustment

The Summit Racing 4-port fuel pressure regulator is designed to feed your engine for maximum performance. The regulator is crafted from billet aluminum and anodized, offering an appealing aesthetic under the hood to match its performance. It has a linear rising rate of 1:1 up to 20 PSI of boost, and a rate of 0.75:1 once 20 PSI is exceeded.

The regulator is suitable for carbureted or EFI applications and can be easily installed and adjusted to fine-tune and optimize performance. The Summit Racing 4-port fuel pressure regulator is available in two pressure ranges: 1.5-25 psi (part number SUM-220058) and 30-100 psi (part number SUM-220059). Both options feature a return style, inline configuration, and black anodized finish.

To install the regulator, follow these steps:

• Refer to the instruction sheets provided by Summit Racing for your specific part number.
• Ensure the regulator is properly sized and fitted for your engine and fuel system.
• Mount the regulator in a suitable location, considering accessibility for future adjustments.
• Connect the regulator to the fuel lines, ensuring secure and leak-free connections.
• Secure any necessary fittings, such as the boost/vacuum reference port and mounting bracket.

To adjust the regulator, you can:

• Refer to the instruction sheets and your vehicle's specifications to determine the desired fuel pressure setting.
• Use the provided adjustment mechanism on the regulator to achieve the desired fuel pressure. This may involve turning a screw or knob to increase or decrease pressure.
• Verify the fuel pressure with a gauge to ensure it is within the optimal range for your engine.
• Fine-tune the adjustment as needed to dial in the performance of your engine.

Note: Always refer to the instructions and specifications for your specific vehicle and regulator for accurate installation and adjustment procedures.

Linear rising rate

The Summit Racing 4-Port Fuel Pressure Regulator has a linear rising rate of 1:1 up to 20 PSI of boost, and a rate of 0.75:1 once 20 PSI is exceeded. This means that for every 1 PSI increase in boost pressure, the fuel pressure will also increase by 1 PSI. This is ideal for maintaining a constant pressure differential between the inlet and outlet of the injector.

A rising rate fuel pressure regulator is used to regulate fuel pressure, which is key for all EFIs (electronically fuel injected engines). The regulator maintains the precise pressure required and returns any fuel that is unnecessary to that task back to the fuel tank.

At times of high acceleration, the engine needs more fuel. A rising rate regulator can be used to temporarily increase fuel pressure on demand. By having it react to engine vacuum (hose to the plenum), it will inject more fuel, even though the injector duration remains the same.

The Summit Racing 4-Port Fuel Pressure Regulator is designed for carbureted or EFI engines and will easily install and adjust to fine-tune and dial-in performance.

Return style regulators

Return-style regulators, also called ""bypass" regulators, are a common choice for a performance fuel system. Here's how they work:

Fuel from the pump enters the inlet and flows past the "bypass valve," which is held closed by a spring. The fuel exits the outlet port and flows to the fuel bowls or fuel rails. As pressure increases, it pushes against the spring through a diaphragm. When the pressure gets high enough, the bypass valve starts to open, redirecting some fuel back to the tank, which reduces the pressure in the system. As the pressure drops, the spring closes the valve, allowing the pressure to rise again. This process maintains the set fuel pressure.

You can adjust the pressure with the nut/bolt on top of the regulator. Most regulators also have a vacuum/boost reference port. Connect it to the carburetor or intake (check your instructions). This allows manifold pressure to affect the regulator diaphragm, so the regulator will adjust fuel pressure based on boost pressure, ensuring proper fuel delivery.

A return-style regulator offers several benefits over blocking regulators:

• Faster reaction to changes in engine load
• More consistent and accurate fuel pressure
• Reduced Lean Condition spikes
• Easier on electric fuel pumps
• Reduced heat, noise, and longer pump life due to less pressure and constant fuel circulation
• Reduced risk of Vapor Lock and increased power

However, there are also some drawbacks:

• Requires extra plumbing and additional hoses and fittings for the Return Line
• Cannot be used in some fuel systems, e.g., a nitrous system with multiple regulators set at different pressures

Summit Racing offers a range of return-style fuel pressure regulators, such as the Summit Racing™ 4-Port Fuel Pressure Regulators (SUM-220058 and SUM-220059), which are crafted from billet aluminum and anodized for a great look under your hood. They offer easy installation and adjustment to fine-tune your performance.

Fuel pressure settings

The Summit Racing 4-Port Fuel Pressure Regulators are designed to feed your engine for maximum performance. The regulator's pressure settings can be adjusted to fine-tune and optimise your engine's performance.

The regulators have a linear rising rate of 1:1 up to 20 PSI of boost. Once the boost exceeds 20 PSI, the rate changes to 0.75:1. The regulator's pressure range is classified as low pressure (less than 20 psi) and high pressure (more than 20 psi).

The specific pressure settings for your engine will depend on various factors, such as the type of carburetor and its application. It is important to set the correct fuel pressure to ensure your engine runs smoothly and avoid issues such as flooding or fuel starvation.

For example, the Summit Racing™ 4-Port Fuel Pressure Regulator SUM-220058 has a pressure range of 1.5-25 psi, while the SUM-220059 model offers a higher pressure range of 30-100 psi.

Frequently asked questions