Radium 8AN ORB Direct Mount Fuel Pressure Regulator (Green)

The Radium Engineering Direct Mount Regulator (DMR) is a compact high performance adjustable fuel pressure regulator that is capable of managing high flow fuel systems. It's compact package fits in tight spaces but does not compromise on performance.

The main inlet port on the regulator is female threaded for 6AN ORB. A swiveling double ended adapter (see photos) is included which allows the regulator to be used in any compatible 8AN ORB fuel rail port, such as those found Radium Engineering fuel rails. 

The bottom return port is threaded for 6AN ORB. The provided 90-degree 6AN ORB to 6AN male fuel return fitting can swivel 360 degrees, permitting a multitude of mounting configurations. Other adapter fittings can be installed in the return port if needed (sold separately).

The regulator has two 1/8' NPT side port locations that can be used with a pressure gauge (such as the Radium fuel pressure gauge), transducer, temperature probe, etc. Two 1/8' NPT plugs are provided so you can plug these if not used.

Fuel Compatibility:

This Radium regulator is suitable with all gasoline types including unleaded, leaded, oxygenated, and pre-mixes. Furthermore, they are compatible with alcohol blends of fuel including methanol, ethanol, and E85.

How to adjust fuel pressure with this regulator:

Radium fuel pressure regulators feature the first tool-less pressure adjustment. A jam nut and set screw are no longer required. With a simple turn of the knob, pressure will be increased or decreased. Additionally, there are no inherent air (vacuum/boost) leaks through the threads that traditionally a smoke detector would pick up.

1:1 Rising rate vacuum reference:

Radium regulators feature a 360-degree swiveling vacuum reference port that is double O-ring sealed. This is the first in the industry. It permits the installer to quickly point the vacuum fitting in any direction with no tools required.

There are 4 interchangeable 10-32 threaded vacuum port fittings provided to cover all scenarios.

• Barbed Fitting: A black zinc-plated 3/16" (5mm) barb machined from high strength steel that is compatible with the following vacuum hoses: 5/32" (4mm), 3/16" (5mm), and 7/32" (6mm)
• 3AN Male Fitting: A black zinc-plated adapter machined from high strength steel that is compatible with 3AN hose ends
• Push-To-Connect: A nickel-plated brass fitting with Buna-N O-rings that is compatible with hard plastic 1/4' OD tubing

• Vacuum Plug: A black oxide stainless steel screw that is used to maintain a constant (non dynamic) fuel pressure. Beginning in the mid 1990s, vehicle manufacturers started transitioning to returnless fuel systems to lower EVAP emissions. To keep temperatures lower, these regulators are mounted inside the tank and do NOT have the ability to be vacuum referenced. This plug would be required in this scenario.

  NOTE: When installing the vacuum fitting, it is recommended to use a wicking medium-strength thread locker.

Fuel pressure stability:

With years of track and bench testing data, the Radium regulators have been refined to optimize pressure management. A newly designed single stainless steel return orifice generates laminar flow that enhances stability control.

Minimum Pressure: 18.5psi (1.3bar)
Maximum Pressure: *N/A

*This is rhetorical. The maximum pressure is dependent on the relief valve inside the pump or the maximum current the fuel pump controller allows.

Included: