Adjusting Fuel Pressure On Msd Atomic Efi Systems

The MSD Atomic EFI is a throttle-body EFI system that is highly customisable and can be used with a variety of fuel systems. The fuel pressure can be changed by adjusting the regulator, which is located between the outlet of the throttle body and the return inlet of the fuel tank. The recommended fuel pressure for the MSD Atomic EFI is between 42 and 48 psi, but it can be adjusted higher or lower depending on the specific application and fuel system used. It is important to note that the fuel pressure should not be too high or too low, as this can cause the engine to run too rich or too lean, respectively. Additionally, it is crucial to ensure that the fuel system is properly configured and all connections are secure to prevent leaks and ensure optimal performance.

Vacuum leaks

When troubleshooting a rough idle, it is important to check for vacuum leaks first. Incorrectly adjusted throttle blades can also cause rough idling, so it is worth checking and adjusting these after addressing any vacuum leaks.

If you suspect a vacuum leak, there are a few things you can do to try and locate the source. One method is to spray around with a starter fluid to see if there is any change in the engine's performance. Another way to check for leaks is to use a vacuum gauge; hook it up to the brake booster port and read the vacuum level. A reading of around 17 inches of mercury (Hg) is considered good.

In addition to vacuum leaks, other factors such as fuel pressure, ignition issues, and exhaust leaks can also contribute to poor engine performance. It is important to consider these factors and make the necessary adjustments to fine-tune your engine.

Injector codes

One common injector code is the "INJ DC" or excessive injector duty cycle code. This code suggests that the injectors are being overworked and requires immediate attention. To correct this issue, the fuel pressure may need to be increased, as recommended in the owner's manual. However, it's important to exercise caution and not exceed the recommended fuel pressure specifications.

Another aspect to consider is the fuel pressure regulator. Some MSD Atomic EFI systems may require an external fuel pressure regulator, while others have an internal regulator. The regulator helps maintain the set fuel pressure at the throttle body. It's important to follow the instructions provided by MSD for the specific fuel injection system being used.

Additionally, vacuum leaks can impact the performance of the fuel injection system. It's crucial to ensure that there are no vacuum leaks, as they can affect the engine's idle quality and overall performance. Properly adjusting the throttle blades and checking for vacuum leaks are important steps in troubleshooting injector codes.

Furthermore, the size and flow rate of the fuel injectors play a significant role in meeting the engine's fuel demands. If the engine requires a higher fuel flow rate, larger injectors may be necessary. It's important to calculate the engine's fuel requirements and select the appropriate injector size to ensure optimal performance.

In conclusion, injector codes are an essential aspect of the MSD Atomic EFI system, providing insights into the performance of the fuel injectors. By monitoring these codes and making necessary adjustments, such as fuel pressure modifications, fuel regulator settings, and addressing vacuum leaks, one can ensure the optimal performance of their MSD Atomic EFI fuel injection system.

Fuel pressure regulator

The MSD Atomic EFI fuel injection system is a popular choice for those looking to convert from a carburetor to fuel injection. It includes a throttle body, a power module, and a handheld controller for initial setup and engine data monitoring.

The fuel pressure regulator is an integral part of the MSD Atomic EFI system, and it is included with the kit. The regulator is of the back-pressure style, which "bleeds off" excess fuel through the return line to maintain the set fuel pressure. It is recommended to set the fuel pressure between 40-48 psi, with some users suggesting an optimal pressure of around 70 psi.

The fuel pressure regulator also features a vacuum nipple. This vacuum connection is not necessary for all setups. If the injectors are above the throttle plates and are only exposed to atmospheric pressure, the vacuum line is not required. However, if the injectors are below the throttle plates or inside the intake manifold, the vacuum reference is needed.

It is important to note that the MSD Atomic EFI system can be used in a returnless setup, but it is not recommended due to potential vapor lock issues. A return line setup with a fuel pressure regulator is generally preferred to ensure optimal fuel pressure and engine performance.

Fuel pump output

The MSD Atomic EFI Fuel Pump Kit is designed to be the easiest way to convert to electronic fuel injection. The kit includes everything you need to support up to 525 horsepower engines.

The kit includes an external inline electric fuel pump with a capacity of 43 gallons per hour, a pre-filter, a post-filter, 15 feet of 3/8" fuel line, and mounting hardware. The pump has a 3/8" inlet and outlet. The kit is designed to work with your vehicle's existing sending unit in the gas tank, so there's no need to remove the fuel tank for installation.

The fuel pump output pressure should be set at a minimum of 40-48 psi, according to the instructions. However, some users have reported better performance at higher pressures of around 70 psi. The pump is rated for up to 525 HP and 1000 CFM.

The fuel pump is part of a complete system that includes the throttle body, which has an internal regulator. The regulator can be set to maintain the desired fuel pressure at the throttle body, ensuring a stable fuel supply to the engine.

The MSD Atomic EFI system also includes advanced self-learning properties to maximize engine output. It is important to note that the system requires proper tuning to function optimally.

Fuel system components

The MSD Atomic EFI fuel injection system is designed to be a simple bolt-on replacement for carbureted engines. It features an integrated ECU and throttle body, which reduces the amount of wiring and connections required during installation. The ECU houses the TPS, MAP, IAT, and fuel pressure sensors, further simplifying the setup.

The fuel delivery system consists of four 80 psi injectors that utilise a stainless steel ball and seat metering method for effective internal sealing. The injectors are mounted between the housing and the cast fuel rails, ensuring a secure fit. The system also includes a fuel pump, with a recommended operating pressure of 40-48 psi, and a fuel filter.

The MSD Atomic EFI has a self-learning capability, which helps maintain smooth engine performance in various conditions. It comes with a wide-band oxygen sensor and a coolant temperature sensor, as well as a throttle position sensor and a map sensor. The system can support engines up to 525-625 horsepower.

Frequently asked questions