F-Series AFS DIY Kit

F-Series (F3x/F2x) B58 Stand Alone AFS™ – DIY Kit

For use with a stock OEM pump. If you have an existing Stage 3, Stage 4 or 4.5 click here.

The Precision Raceworks F-Series (F3x/F2x) B58 Stand Alone AFS™ DIY Kit 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 on modern BMW's, 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!

This DIY kit supplies the dual-output billet top hat, in-tank plumbing, auxiliary pump of your choice, and the complete auxiliary-side line set so you can build a dedicated AFS™ on the F-Series B58. Both the DI circuit and the auxiliary circuit are protected by a 10 micron USA made Micro-glass fuel filter.

Features & Benefits

• Billet Aluminum top hat with 2 feed ports and 1 return port
• Dedicated 10 micron USA made Micro-glass fuel filter on the DI side
• Dedicated 10 micron USA made Micro-glass fuel filter on the auxiliary side
• Dedicated auxiliary fuel pump for port injection 
• Aux pump mounting hardware and in-tank plumbing included
• Fully adjustable 1:1 scaling billet fuel pressure regulator
• Smooth bore high flow PTFE auxiliary fuel feed & return lines (AN6)
• All billet connections for both fuel line fittings and 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 DIY kit comes with all** necessary components to build a dedicated fuel system for port injection. Featuring a single Walbro 450 (F9000274) auxiliary fuel pump which flows 425LPH at 3 bar.
• AFS.450
  The AFS.450 DIY kit comes with all** necessary components to build a dedicated fuel system for port injection. Featuring a single Walbro 525 (F90000285) auxiliary fuel pump which flows 450LPH at 3 bar.
• AFS.460
  The AFS.460 DIY kit comes with all** necessary components to build a dedicated fuel system for port injection. Featuring a single Walbro 535 (F9000295) auxiliary fuel pump which flows 460LPH at 3 bar.

DIY Kit Includes

• F-Series billet aluminum top hat with 2 feed ports and 1 return port
• 10 micron USA made Microglass fuel filter for the DI side
• Auxiliary pump of your choice 
• Auxiliary pump mounting hardware
• In-tank plumbing
• Auxiliary fuel feed & return lines
• Fully adjustable 1:1 scaling billet fuel pressure regulator
• 10 micron USA made Microglass fuel filter for the auxiliary side
• Mounting hardware for the auxiliary components.

If your tuner wishes for you to have a Solid State Relay, we recommend using our kit here.

*Installation of this kit requires cutting and splicing factory wiring to the connectors included. Plug and play harness options are not available for F-Series AFS™.

**The AFS™ kits are designed for use with a port injection kit where the fuel rail is mounted above the manifold. To use with a plate style spacer PI, please reach out to us directly at 713-770-6977 or sales@precisionraceworks.com