SKU: 7354413347

BMW G8x M3, M4 & G2x M340i, M440i Stand Alone Auxiliary Fuel System

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Description

BMW G8x M3, M4 & G2x M340i, M440i Stand Alone Auxiliary Fuel SystemThe Precision Raceworks BMW G8x M3, M4 & G2x M340i, M440i Stand Alone Auxiliary Fuel System is the highest performing and most stable low pressure fuel system on the market! Forget about how things have been done and embrace the benefits of dedicated fueling for your port injection! Since direct injection came out for BMW, enthusiasts have been adding port injection. With this came the need to upgrade the low pressure fuel system to keep up.

The Precision Raceworks BMW G8x M3, M4 & G2x M340i, M440i Stand Alone Auxiliary Fuel System is the highest performing and most stable low pressure fuel system on the market! Forget about how things have been done and embrace the benefits of dedicated fueling for your port injection!

Since direct injection came out for BMW, enthusiasts have been adding port injection.  With this came the need to upgrade the low-pressure fuel system to keep up.  Historically this was done by increasing the output of the main fuel system.  Unfortunately, the main fuel pump is controlled using PWM by a factory programmed controller designed to reduce output when target fuel pressure (typically 5 bar) is exceeded, creating a constant battle when pumps are added or upgraded.  This limits upgraded fuel pumps from performing to their full potential.

Additionally, the high pressure pump control system dumps fuel back into the low pressure system at high pressure low volume resulting in oscillations of the low pressure fuel system.  Because of this the DI system in the car is required to constantly make corrections to keep target AFR in check.

With this stand-alone low-pressure fuel system dedicated to your port fueling that is a thing of the past!  Get rock solid fuel pressures at any pressure, run fuel pressures which are 1:1 scalable to boost pressure, flow more fuel with dedicated lines, run smaller injectors and still get more fuel than you did with large injectors (allowing for higher resolution), put less demand on the car’s DI system to correct for fluctuations in pressure, even your tuner will be grateful as the system makes tuning of port fueling even easier and more accurate, the list of benefits goes on and on!

Features & Benefits

  • Billet Aluminum top hat with 3 high flow fuel ports
  • Dedicated fuel pump(s) for port injection system
  • Optimal pump location resistant to fuel slosh under acceleration
  • Fully adjustable 1:1 scaling billet fuel pressure regulator
  • 10 micron USA made Microglass fuel filter (Ideal for E85)
  • Smooth bore high flow PTFE fuel feed & return lines (AN6)
  • All billet connections for both fuel line fittings and top-hat
  • Plug and play connectors inside and outside* the top hat
  • Configurable pump activation harness (see instructions for more details)
  • Increased injector flow (when using 1:1 regulator feature vs static)
  • Compatible with all stock or upgraded primary fuel pumps
  • Easily expandable and upgrade-able for more fuel
  • All components and parts feature 100% Ethanol Compatibility

Models & Configurations

  •  AFS.425
    The AFS.425 dedicated auxiliary fuel system comes with all** necessary components to provide dedicated fuel system for port injection.  Featuring a single Walbro 450 (F9000274) fuel pump which flows 425LPH at 3 bar.
  •  AFS.460
    The AFS.460 dedicated auxiliary fuel system comes with all** necessary components to provide dedicated fuel system for port injection.  Featuring a single Walbro 535 (F9000295) fuel pump which flows 460LPH at 3 bar.
  •  AFS.640
    The AFS.640 dedicated auxiliary fuel system comes with all** necessary components to provide dedicated fuel system for port injection.  Featuring Two Walbro 450’s (F9000274) fuel pumps with a combined flow of 640LPH at 3 bar.
  •  AFS.745
    The AFS.745 dedicated auxiliary fuel system comes with all** necessary components to provide dedicated fuel system for port injection.  Featuring One Walbro 450 (F900074)  & One Walbro 535 (F9000295) fuel pumps with a combined flow of 745LPH @ 3bar.
  •  AFS.800
    The AFS.800 dedicated auxiliary fuel system comes with all** necessary components to provide dedicated fuel system for port injection.  Featuring Two Walbro 535’s (F9000295) fuel pumps with a combined flow of 800LPH at 3 bar.

*At time of install some wiring in the car may need to be cut and spliced to connectors included in this kit

**Male AN8-ORB to Female AN6-ORB adapter may be required for compatibility with some fuel rails (not included in kit)

Fitments

  • Bmw M3 2021 to 2024
  • Bmw M340i 2019 to 2024
  • Bmw M4 2021 to 2024
  • Bmw M440i 2020 to 2024

Specifications

AFS.425

    • Pump flow 43.5psia : 425lph
    • Recommended base pressure: 43.5psig
    • Maximum Fuel Pressure: 110psig
    • Number of Fuel Output Ports: 2
    • Number of Fuel Return Ports: 1
    • Pump 1: Walbro 450 (F90000274)
    • Pump 2: N/A
    • Available (unused) Electrical Connections: 4*
    • Total System Weight:

          AFS.460

            • Pump flow 43.5psia : 460lph
            • Recommended base pressure: 43.5psig
            • Maximum Fuel Pressure: 110psig
            • Number of Fuel Output Ports: 2
            • Number of Fuel Return Ports: 1
            • Pump 1: Walbro 535 (F90000295)
            • Pump 2: N/A
            • Available (unused) Electrical Connections: 4*
            • Total System Weight:

           

            AFS.640

              • Pump flow 43.5psia : 640lph
              • Recommended base pressure: 43.5psig
              • Maximum Fuel Pressure: 110psig
              • Number of Fuel Output Ports: 2
              • Number of Fuel Return Ports: 1
              • Pump 1: Walbro 450 (F90000274)
              • Pump 2: Walbro 450 (F90000274)
              • Available (unused) Electrical Connections: 2*
              • Total System Weight:

              AFS.745

                • Pump flow 43.5psia : 745lph
                • Recommended base pressure: 43.5psig
                • Maximum Fuel Pressure: 110psig
                • Number of Fuel Output Ports: 2
                • Number of Fuel Return Ports: 1
                • Pump 1: Walbro 535 (F90000295)
                • Pump 2: Walbro 450 (F90000274)
                • Available (unused) Electrical Connections: 2*
                • Total System Weight:

                    AFS.800

                      • Pump flow 43.5psia : 800lph
                      • Recommended base pressure: 43.5psig
                      • Maximum Fuel Pressure: 110psig
                      • Number of Fuel Output Ports: 2
                      • Number of Fuel Return Ports: 1
                      • Pump 1: Walbro 535 (F90000295)
                      • Pump 2: Walbro 535 (F90000295)
                      • Available (unused) Electrical Connections: 2*
                      • Total System Weight:
                    Shipping Notes
                    • Free Standard Shipping on $100+ Orders to the USA.
                    • Except Preorder products are shipped in 48 hours.
                    • Delivery to the USA:
                    1. Standard Shipping : 3-10 business days
                    • If time is of the essence, please consider selecting expedited delivery for faster service.
                    Exchange/Return Notes
                    • We offer a 30-day return/exchange service after receiving.
                    • Final sale items are not eligible for returns or exchanges.
                    • To process your return/exchange, please contact us at [email protected]
                    • Please click here for more details>>> Return & Exchange Policy
                    SKU: 7354413347

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                    Roderick
                    Pawtucket, US
                    ★★★★★ 5
                    Great Purchase
                    Size: 12, Color: Black
                    These shoes are great. They look great and extremely comfortable.
                    WAS THIS REVIEW HELPFUL?YesReportShare
                    Reviewed in the United States on May 10, 2026
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                    Isaiah O
                    Birmingham, US
                    ★★★★★ 5
                    Comfortable, Easy to Clean, and Held Up at Coachella
                    Size: 12, Color: White, Size: 12, Color: White
                    I’m really happy with this purchase. The shoes are very comfortable, and the product description is accurate. I followed the sizing recommendation based on my foot type and went one size up—they fit perfectly. I bought these for Coachella, and they definitely held up. I was on my feet all day, and they stayed comfortable the entire time. What impressed me most is how easy they were to keep clean. At the end of each day, I was able to wipe them down and maintain their whiteness without much effort. Once I got home, I gave them a deeper clean, and they honestly looked as good as new. Even the laces cleaned up easily. Now I’ve transitioned them into my regular work shoes, and they still look great. Overall, I’m very satisfied with this purchase and would definitely recommend them.
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                    Reviewed in the United States on May 4, 2026
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                    Verified Purchase
                    Hawaiian
                    Fort Morgan, US
                    ★★★★★ 4
                    Great shoes that are well made, lite weight, and comfortable.
                    Size: 12, Color: Brown
                    Just received my 2nd pair of shoes from Bruno Marc in a size 12. These are really lite and comfortable. It can be dressed down to be a casual shoe or dressed up with a nice suit. These run true to size so I ordered my usual size 12 and the fit was perfect. Being my 2nd pair of Bruno Marc's, I like the quality of their shoes and each shoe is described appropriately on fit and comfort. Insole of these shoes were awesome and provided soft comfort on the feet along with a slight arch support too. Will definitely consider ordering more Bruno Marc shoes in the future.
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                    Reviewed in the United States on March 11, 2025
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                    Verified Purchase
                    JCMIV63
                    San Leandro, US
                    ★★★★★ 5
                    Cushioned, comfortable, stylish and a rubber sole!
                    Size: 10, Color: Brown
                    These shoes check multiple boxes for me, comfortable, cushioned, rubber sole and stylish. As my feet grow old and worn out, I'm on a constant search for comfortable, cushioned shoes that are suitable for work and dressier occasions. I have tried many expensive shoes that look great but either lack cushioning, arch support and or comfort. One of the nice things is these shoes have a rubber sole, where most cushioned shoes have the foam soles which are great, but they tend to lack grip particularly when its damp/wet. They have average arch support, but the insole is removable and I put my own cushioned arch support. Love these!
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                    Reviewed in the United States on April 6, 2026
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                    DDD Projects
                    Natrona Heights, US
                    ★★★★★ 5
                    OG Style
                    I am a big fan of Bruno Marc shoes. Over the years they have provided comfortable and affordable boots and shoes. These blue, tan and white soled dress sneakers are no exception. They have a nice finished look that makes them both causal and dressy. The lightweight style is still warm enough for colder mid-west winters. The box of the toes is wide and comfortable. The insole is well padded and a pleasure to wear. This is another fine pair of shoes to add to my collection and yours.
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                    Reviewed in the United States on January 14, 2026

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