Fuel Rail Crossover™ (FRx)

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7.3L Diesel Fuel Rail Crossover™ (FRx) 99-03 Powerstroke

"The Prescription For Your Fuel System Needs®"

Our 2nd Generation FRx™ System utilizes Eaton Aeroquip® 304 Stainless Steel Braided lines covered with a groundbreaking protective layer of HYTREL® from DuPont.

The FRx™ was made to solve the 'deadhead' fuel rail issue on the 99-03 Powerstroke engine by connecting the two heads and allowing a metered return you allow the air another return path, rather than forcing it through your injectors. This product was designed to eliminate the need to cut your return line and use compression fittings, so that it is a true bolt on system. We have also machined the FRx™ block to provide from stock to 72 psi of fuel pressure depending on which spring you choose to install it with. By using our kit and eliminating the air in the fuel system you can experience smoother, quieter idle, less cackle, and better throttle response among other things. You will also be increasing your injector life as well by utilizing the FRx™ and creating a regulated return back to the tank. Protective covers are also pre-installed to prevent chaffing of engine components from the SS braided line. These covers are also great if you want to keep the system looking OE and not draw attention to it once installed.

Included:                                                                                        Techical Info:
- FRx™ System                                                                               - Exceeds SAE 100R14A
- 3 Springs for adjusting Fuel Pressure                                              - Rated for commercially produced B100
- Viton O-ring                                                                                  - Temperature Rated -100˚F to +450˚F
- Parker® Fuel Sleeve                                                                      - Max. Working Pressure 3000 psi
- 2 Stainless mounting bolts                                                             - Minimum Burst Pressure 12000 psi
- Custom 9/32" socket

Fuel pressure spring settings 
55-60 psi  silver spring
61-65 psi  gold spring *Recommended 
66-72 psi  black spring

Riffraff Diesel Performance is committed to 100% Made in the USA. All materials are from USA resources. Every machining step is performed in the USA. Every component is assembled in the USA.


1999-2003 7.3L Powerstroke with stock fuel bowl
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  • 5
    Fuel rail crossover

    Posted by Ryan on Feb 1st 2024

    Great kit easy install

  • 5
    An underratted addition

    Posted by Moto on Jan 11th 2024

    I thought my truck stalled, that is how smooth and quiet the idle is now. I went with the medium spring and its a night and day difference. Delivery of power is much smoother as well. Also the best part in my opinion, they give you the square socket to remove your fuel plugs. Excellent product!

  • 5
    Surprised by results

    Posted by Ryan on Jan 3rd 2024

    I was surprised how much it quieted down and start-up and idle. Routing is not fun, hard to say about performance becuase my truck is all stock I added this as part of a repair for a fuel leak

  • 5

    Posted by Chuck on Dec 28th 2023

    Definitely is running smoother on idle.

  • 5
    Riffraff FRx

    Posted by Mike on Dec 26th 2023

    Installed this on my 2000 7.3 when my fuel bowl seals finally started puking diesel. So far I’ve been really happy with it. For those of you reading that this is a performance mod- it is not. You will not notice any “gains” or “throttle response” like some of these reviews say. However, you absolutely can tell the difference in engine sound and injector noise. The truck sounds way healthier overall, particularly at idle and at cruising speed. This is a beneficial longevity mod that should extend injector life. I also paired with the Riffraff HPx oil crossover. Can’t say which one helped more, I would definitely do them both together at the same time. Highly recommend both products.

  • 5
    Riffraff Quality

    Posted by Cyrus Mohit on Oct 3rd 2023

    Great upgrade to an OEM fuel bowl system.

  • 5
    Best 7.3 Mod

    Posted by Jason on Sep 10th 2023

    Should have been this way from the factory. My injector are quieter and smoother. Good instructions and the special socket was even included in the kit.

  • 5
    Fuel rail crossover

    Posted by Ben M on Jul 22nd 2023

    Definitely a great purchase for my 7.3 Powerstroke. Install was simple and quick. Literally had it in under 15 minutes. Best upgrade to date. Would recommend this to anyone with a 7.3

  • 5
    Fuel rail easy install

    Posted by Guy on Jul 21st 2023

    Not a difficult install at all. Everything fit perfectly. Follow the video instructions.

    I have waited a month to review. My observation is that it did quiet the motor at idle. It also made a slight drivability improvement; a pinch better throttle response. Used recommended spring for a stock motor. I have no chip, and a stock compressor wheel.