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Our Price: $279.95


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99-05 Mazda MX-5

This kit features a new adjustable fuel pressure regulator (FPR) that is compatible with all fuel pump hangers including the factory returnless system found in the NB chassis. As shown below, the FPR is mounted near the EVAP charcoal canister using OEM threaded studs.

The OEM fuel feed line from the fuel pump to the fuel filter is reused and unaltered. However, two new 6AN fuel lines (shown below) are provided to and from the FPR.

A fuel pressure gauge (shown above) mounts adjacent to the FPR on the feed line for easy adjustment. A stainless steel SAE quick connect plug is provided to block off the "TEE" on the OEM feed line.


The RA-series regulator features 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. 
1. 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).
2. 3AN Male Fitting: A black zinc-plated adapter machined from high strength steel that is compatible with 3AN hose ends.
3. Push-To-Connect: A nickel-plated brass fitting with Buna-N O-rings that is compatible with hard plastic 1/4" OD tubing.
4. Vacuum Plug: A black oxide stainless steel screw that is used to maintain a constant (non dynamic) fuel pressure. To keep fuel pressure the same as the OEM MX-5 fuel system, this plug should be used.

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

This system 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. 

1. No permanent modifications are required.
2. Compatible with Radium Engineering 20-1020 Mazda MX-5 Fuel Hanger
2. Compatible with OEM fuel hanger (instructions detail how to bypass the OEM FPR).

-MPR-RA Fuel Pressure Regulator
-Fuel Pressure Gauge, 0-100psi 
-Stainless Steel Mounting Bracket
-Anodized Aluminum Fittings
-SAE Quick Connect Fittings
-Hose Clamps and Hardware
-6AN (3/8") Fuel Hose

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