Now featuring Plug & Play connectors! It is no longer necessary to cut your factory harness! The Precision Raceworks G8x 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)
Note: Male AN8-ORB to Female AN6-ORB adapter may be required for compatibility with some fuel rails (not included in kit). 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
AN8 ORB to AN6 Female ORB - For feed input side (by firewall)
AN8 ORB to AN6 Male Flare - For return side (front of car)
Vehicles Supported
BMW G8X M3/M4, including Competition
