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LAST UPDATED: February 12, 2020

Best Aftermarket EFI Systems: Optimum Power and Efficient Fuel Delivery

These top aftermarket EFI systems will provide optimum power and efficient fuel delivery for your vehicle

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PUBLISHED ON February 12, 2020

EFI (electronic fuel injection) systems are becoming more and more popular because of their efficiency and optimum power. Compared to carbureted motors, they are great because they deliver better fuel economy. Many people think that conversion from carburetor to EFI is a really difficult task, but it is not as hard as it sounds. If you know which system is best suited for your needs, then you will be able to make an informed decision. Our top picks for the best aftermarket EFI system are outlined in the guide below.

  • Best Overall
    New Holley Sniper 550511 EFI Kit
    New Holley Sniper 550511 EFI Kit
    Summary
    Summary
    This Holley 550511 EFI kit can support up to 650 HP. It comes with a handheld EFI monitor and a self-tuning ECU.
    Pros
    Pros
    It features an easy-to-use self-tuning system. It also includes easy-to-replace oxygen sensors. It eliminates cold start, vapor lock, and hesitation issues.
    Cons
    Cons
    The master kit version that comes with a complete fuel system is more expensive. Assembling the kit requires automotive knowledge.
  • Best Overall
    New Holley Sniper 550511 EFI Kit
    New Holley Sniper 550511 EFI Kit
  • Best Value
    FiTech 30021 Go EFI System
    FiTech 30021 Go EFI System
    Summary
    Summary
    This EFI kit comes with everything you need to maintain the classic look of your carburetor by hiding the injectors.
    Pros
    Pros
    Eliminates vapor lock, flooding, and cold start issues. The more you drive, the more it adapts to your driving style. It can be mounted wherever you want to maintain the classic look of your carburetor.
    Cons
    Cons
    Decent mechanical abilities are required for installation. It doesn’t come with a fuel system. 
  • Best Value
    FiTech 30021 Go EFI System
    FiTech 30021 Go EFI System
  • Honorable Mention
    MSD 2900 Atomic EFI Master Kit
    MSD 2900 Atomic EFI Master Kit
    Summary
    Summary
    Weighing only 16.14 pounds, the MSD 2900 Atomic EFI Master kit can easily fit multiple models.
    Pros
    Pros
    It includes single fuel line self-tuning and built-in sensors.  There is no need for bulky ECU. It has only eight wirings. A laptop is not needed for programming.
    Cons
    Cons
    Battery charger needs to be plugged in for a long time. The computer tends to drain the battery faster.
  • Honorable Mention
    MSD 2900 Atomic EFI Master Kit
    MSD 2900 Atomic EFI Master Kit

    EFI (electronic fuel injection) systems are becoming more and more popular because of their efficiency and optimum power. Compared to carbureted motors, they are great because they deliver better fuel economy. Many people think that conversion from carburetor to EFI is a really difficult task, but it is not as hard as it sounds. If you know which system is best suited for your needs, then you will be able to make an informed decision. Our top picks for the best aftermarket EFI system are outlined in the guide below.

    Best Aftermarket EFI Systems Reviews & Recommendations 2020

    Best Overall

    Holley didn’t cut corners when it comes to upgrading the look of the Sniper 550511 over other Holley EFI systems, and that’s why it has a tougher look to it. The unit is made from cast aluminum with a black finish, and the injectors are enclosed in the unit while the ECU is mounted externally. This keeps the wiring neat since almost everything is built into one unit. Also integrated into the unit is an ignition timing control, a coil driver, and a pre-set fuel pressure regulator. 


    The unit is rated for up to 650 horsepower, and is designed to replace any square bore or spread bore style four-barrel carburetor. What's more, it comes with a handheld, full touchscreen monitor, which you can use to tune the EFI system as you please. 


    The main issue we take with this kit is that it doesn’t come with a fuel system, which translates to extra costs on your end if you decide to buy the master kit with the fuel pump. Also, you need decent automotive knowledge to install this kit. Despite that, it’s recommended for nearly any carbureted vehicle including off-road trucks, street rods, and muscle cars. 

    Best Value

    The FiTech 30021 has an innovative patented design that maintains the classic carburetor look by hiding the injectors within the structure and having an externally-mounted ECU. This self-tuning fuel injection system is rated for up to 550 horsepower, and is designed to eliminate cold start issues, vapor lock, hesitation, and flooding. 


    The unit comes with an integrated ignition timing control, and a Bosch 4.2 wideband oxygen sensor for real-time fuel mapping and to help send out information to the ECU. The oxygen sensors come with a clamp-on kit for leak-free installation. In addition, it has a dual bolt pattern, and as a result, can fit in a 4150 square bore flange or a spread bore. Also, you get a high-resolution, full-color touchscreen that will help you set up, tune, and monitor the system.  


    One issue with this model is that you need to have decent mechanical know-how to install the EFI and sensors on numerous points of the engine. Despite that, it’s perfect for an everyday driver since the more you drive the more it adapts to your personal driving style. 

    Honorable Mention

    If you have a muscle car or a hot rod, the MSD 2900 will be a great addition to eliminate cold start and idle issues. This will make your ride feel almost as good as new. This EFI system features advanced self-learning technology, which involves the constant analysis of the engine’s operating conditions to ensure that your vehicle rides smoothly and with minimal issues. It also comes with a monitor that can give you real-time data on the engine’s parameters. 


    The unit has an ECU and sensors built into the throttle body with few wiring connections for a neat system. This also makes the unit less bulky than most EFI systems and, therefore, will be easier to install. Since it’s a Holley master kit, it comes with a complete fuel system including the fuel pump and a single fuel line. After installing it, your vehicle will experience quick starts, a smooth idle, and better throttle response. 


    However, all the frills with this master kit don’t come cheap, as it’s one of the most expensive EFI systems on the market. Also, the ECU and monitor can take a toll on your vehicle’s battery.

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    Benefits of Aftermarket EFI Systems

    • Eliminate the need for a carburetor. Carburetors need to be adjusted mechanically to control the rate of air and fuel flow. However, they can get out of tune over time and risk failure if they aren’t constantly adjusted. EFI systems eliminate the need for a carburetor and continue to regulate the air and fuel flow independently with computations provided by the electronic control unit (ECU). This requires minimal effort on your part in adjusting the system.
    • Lower fuel consumption. EFI systems are more fuel-efficient than carbureted engines. This is because the electronic system constantly adjusts the air to fuel ratio to ensure that optimal levels are delivered. Carbureted engines, on the other hand, may deliver an excess fuel to air ratio, which can lead to more fuel consumption. 
    • Meet the engine’s operating conditions. Your engine may have different fuel or air needs depending on the operating conditions. EFI systems can continuously monitor the operating conditions, and adjust the air to fuel ratio with respect to the ambient temperature, altitude, driving conditions, and other engine requirements such as cold starts or overrun conditions.  
    • Maintain optimal engine performance. Engines that use EFI systems often provide a higher torque than carbureted engines. EFI systems can optimize power, ignition timing, and air to fuel ratios across different engine speeds to promote consistent performance. 

    Types of EFI Systems

    Single Point 

    A single point injector or a throttle body injector has one injector mounted at the throttle body. Fuel is sprayed into the engine in rapid short bursts, which creates a buzzing noise when the engine is started. In comparison to a carburetor, this system has better cold start characteristics and is better at regulating the air to fuel mixture. 

    Multipoint 

    Modern EFI systems typically use a multipoint fuel injector (MPFI). It has a separate fuel injector for each cylinder that sprays fuel directly into each cylinder’s intake port. The injectors can be timed to spray at the same time to all cylinders, or to coincide with the respective cylinder’s intake stroke.  

    Direct 

    A direct fuel injector sprays fuel directly to the combustion chamber, instead of directing it to the intake valve in the case of a gas engine, or a pre-combustion chamber in the case of a diesel engine. This type of injector has a needle valve at the nozzle that’s operated with a solenoid to regulate the pressure of the fluid being delivered into the engine cylinder. Since they are installed so close to the cylinders, they are exposed to more heat and require higher-grade material that can withstand the high temperatures. This is why they are more expensive.  

    Top Brands 

    Holley 

    Holley is an automotive brand that has been making automotive fuel systems for over 100 years. It was birthed by Bradford, Pennsylvania, brothers George and Earl Holley in the late 1800s. Today, the company designs fuel pumps, intake manifolds, EFI systems, and millions of carburetors. A series of mergers throughout the years led to the absorption of other brands under its umbrella including MSD Ignition, Accel, Powerteq, and Racepak. If you would like to try out one of its products, check out the New Holley Sniper EFI Kit.  

    FiTech 

    FiTech is headquartered in Riverside, California, and makes some of the best fuel systems. Apart from making EFI systems, it also makes fuel pumps, fuel filters, fuel pressure gauges, and regulators. The FiTech 30021 EFI System and the FiTech 30005 Easy Street EFI are some of its best EFI systems with innovative designs. 

    Aftermarket EFI Systems Pricing 

    • Under $1,000: The EFI systems within this price range are able to control injection timing according to the speed, load, and the type of driving the vehicle is experiencing. It’s possible to program them to optimize fuel consumption, especially in heavy-duty diesel engines. 
    • $1,000 and up: Most EFI systems are a bit on the expensive side, but that often means you are getting a reliable system that can create a program that will suit your specific application. Therefore, at this price range, you can expect to find an EFI system with a programmable control system that you can monitor and control from a separate handheld monitor. 

    Key Features 

    Type 

    It’s important to consider the type of EFI system you need before buying one. Some types, such as the multi-point injection system, are more precise and better at achieving the ideal air to fuel ratio than the other options. Single-point injection systems are more economical and easier to service. 

    Horsepower

    You should select an injector with a horsepower output that can match the fuel and airflow needs of your engine. This will result in good engine performance despite the ambient temperature, driving condition, or speed. 

    Other Considerations  

    • Compatibility: Any aftermarket part you buy should be compatible with your vehicle to avoid fitting issues. The best way to get a suitable EFI system is to search for one by entering your vehicle’s year, make, and model. If for any reason that doesn’t work, try searching for your vehicle’s OEM part number, which is often indicated on the EFI system. 
    • Fuel: Consider the type of fuel your vehicle uses as well. Some EFI systems come with a complete fuel system consisting of a fuel pump and filters that may not work with both gas and diesel. 
    • Warranty: A warranty serves as proof that the EFI system was designed with high-quality materials. It will help you get a new EFI system or free services from the supplier in case the one you bought stops functioning due to defects in workmanship. 

    Best Aftermarket EFI Systems Reviews & Recommendations 2020

    Best Overall
    New Holley Sniper 550511 EFI Kit

    Holley didn’t cut corners when it comes to upgrading the look of the Sniper 550511 over other Holley EFI systems, and that’s why it has a tougher look to it. The unit is made from cast aluminum with a black finish, and the injectors are enclosed in the unit while the ECU is mounted externally. This keeps the wiring neat since almost everything is built into one unit. Also integrated into the unit is an ignition timing control, a coil driver, and a pre-set fuel pressure regulator. 


    The unit is rated for up to 650 horsepower, and is designed to replace any square bore or spread bore style four-barrel carburetor. What's more, it comes with a handheld, full touchscreen monitor, which you can use to tune the EFI system as you please. 


    The main issue we take with this kit is that it doesn’t come with a fuel system, which translates to extra costs on your end if you decide to buy the master kit with the fuel pump. Also, you need decent automotive knowledge to install this kit. Despite that, it’s recommended for nearly any carbureted vehicle including off-road trucks, street rods, and muscle cars. 

    Best Value
    FiTech 30021 Go EFI System

    The FiTech 30021 has an innovative patented design that maintains the classic carburetor look by hiding the injectors within the structure and having an externally-mounted ECU. This self-tuning fuel injection system is rated for up to 550 horsepower, and is designed to eliminate cold start issues, vapor lock, hesitation, and flooding. 


    The unit comes with an integrated ignition timing control, and a Bosch 4.2 wideband oxygen sensor for real-time fuel mapping and to help send out information to the ECU. The oxygen sensors come with a clamp-on kit for leak-free installation. In addition, it has a dual bolt pattern, and as a result, can fit in a 4150 square bore flange or a spread bore. Also, you get a high-resolution, full-color touchscreen that will help you set up, tune, and monitor the system.  


    One issue with this model is that you need to have decent mechanical know-how to install the EFI and sensors on numerous points of the engine. Despite that, it’s perfect for an everyday driver since the more you drive the more it adapts to your personal driving style. 

    Honorable Mention
    MSD 2900 Atomic EFI Master Kit

    If you have a muscle car or a hot rod, the MSD 2900 will be a great addition to eliminate cold start and idle issues. This will make your ride feel almost as good as new. This EFI system features advanced self-learning technology, which involves the constant analysis of the engine’s operating conditions to ensure that your vehicle rides smoothly and with minimal issues. It also comes with a monitor that can give you real-time data on the engine’s parameters. 


    The unit has an ECU and sensors built into the throttle body with few wiring connections for a neat system. This also makes the unit less bulky than most EFI systems and, therefore, will be easier to install. Since it’s a Holley master kit, it comes with a complete fuel system including the fuel pump and a single fuel line. After installing it, your vehicle will experience quick starts, a smooth idle, and better throttle response. 


    However, all the frills with this master kit don’t come cheap, as it’s one of the most expensive EFI systems on the market. Also, the ECU and monitor can take a toll on your vehicle’s battery.

    Tips

    • If you are planning to use a power adder (such as a supercharger) with your EFI system, you should consider a system that is compatible with your power adder.
    • If your engine is a new build, consider consulting with an engine-building professional before installing an EFI system.
    • EFI systems require higher fuel pressure for efficient operation. Therefore, you should consider upgrading the fuel line to meet the EFI system requirements.
    • Usually, EFI systems do not include a fuel reservoir as compared to a carburetor that has bowls for fuel storage. Therefore, you should also consider installing a fuel tank designed for EFI systems.
    • The location of the fuel pump is very important because it cannot stand higher temperatures for a longer time. Make sure to mount it in a location where it can easily cool down.

    FAQs

    Q: How does an aftermarket EFI system work?

    A: An aftermarket EFI system uses high-pressure fuel delivery to an injector. It also uses computer controls, and overall it increases the power and fuel efficiency of a vehicle. The whole system is controlled electronically.

    Q: What do I need to install an aftermarket EFI system?

    A: You will need throttle bodies, a suitable manifold, a fuel pump with high pressure, injectors, and a filter. Apart from this, you will also need a regulator, a fuel rail kit, ECU, and a return line to the fuel cell.

    Q: Do I need to use air cleaners on an EFI system?

    A: Yes, we recommend you use cleaners. Any standard aftermarket cleaner can be used.

    Final Thoughts

    Our pick for the best overall aftermarket EFI system is the New Holley Sniper 550511 EFI Kit because it provides a great deal of functionality. 

    For a budget-friendly option, you should consider the FiTech 30021 Go EFI System.