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Radium Engineering Fuel Pressure Regulator Kit Black 2008-2021 STI - 20-0965 - Subimods.com

Radium Engineering Fuel Pressure Regulator Kit Black 2008-2021 STI

$256.45
$269.95
$269.95 - $269.95
$269.95
$256.45 - $256.45
$256.45
-5% -5%
9 In Stock, Usually Ships within 1-2 Business Days
SKU 20-0965
by Radium Engineering

DETAILS

This kit is designed for use in the USDM 2008-2019 Subaru WRX STi (EJ257 only) and replaces the OEM fuel pressure regulator and damper assembly, shown below. The factory STi fuel line routing uses a quasi dead-end system that circulates fuel through the regulator, bypassing the engine. Fuel is only routed to the engine when there is demand.

The Radium FPR kit replaces the factory regulator and re-routes fuel to cycle through the engine's rails before reaching the regulator and returning to the tank. This is the preferred fuel line routing by Subaru tuners trying to address stumbling issues. The Radium Fuel Pressure Regulator offers adjustment from 20psi-up with a 1:1 vacuum reference. Interchangeable orifices allow the user to tune the regulator for any fuel pump flow.

The kit installs in the same location as the OEM fuel pressure regulator. Also included are vacuum hose and fittings to re-route the vacuum reference line from the #4 cylinder runner to the intake manifold plenum for a more stable vacuum signal. The optional pressure guage kit 20-0386 can be installed into the unused 8AN ORB port on the regulator, as shown in the attached photos.

Customer Reviews

Based on 3 reviews
67%
(2)
33%
(1)
0%
(0)
0%
(0)
0%
(0)
L
Louie ortiz
Simple

Quick and painless install, bummed that it does not include the gauge in the price but honestly not a deal breaker. Overall great quality to price value.

User picture

Louie,

Thank you for taking the time to leave a 5 Star Review. We are glad to hear that you found the Radium Engineering Fuel Pressure Regulator Kit easy to install. We apologize for any disappointment regarding the gauge not being included, but we are happy to hear that it didn't detract from the overall value. Thank you for choosing Subimods! Enjoy!

Regards,

N
Neri Ayala
Good product

10/10

Neri,

We appreciate the 5 Star Review!

Regards,

I
Ian A.
Wow so good!

The product itself was fantastic. Unfortunately I ordered the regulator and the gauge as separate packages and only found out after I was assembling and installing that the ORB adapter to put them together was not part of either the gauge or the FPR packages. Ordered the adapter on Amazon to get it quicker but once I installed, it made such a huge difference in driveability on my 2020 STI. FBO ~370whp on 93

User picture User picture

Ian,

Thank you for sharing your experience and pics of the Radium Engineering Fuel Pressure Regulator Kit in black for the 2008-2021 STI. I am glad to hear that despite the inconvenience with the separate packages and the missing ORB adapter, once installed, the product made a significant positive impact on the driveability of your 2020 STI! Achieving around 370whp on 93 octane with the full bolt-on setup is fantastic! If you have any more comments or need further assistance, please feel free to reach out. Enjoy!

Regards,

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