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Riffraff Diesel Performance Inc, Engines - Supplies, Equipment & Parts, Eagle Point, OR


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Fuel Rail Crossover™ (FRx)

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Your Price:
$188.81 (You save $8.56)
Part Number:

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

"The Prescription For Your Fuel System Needs®"

We are now shipping our 2nd Generation FRx System that 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 will 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.


- FRx System
- 3 Springs for adjusting Fuel Pressure 
- Viton O-ring 
- Parker® Fuel Sleeve
- 2 mounting bolts
- Instructions

Techical Info:
- Exceeds SAE 100R14A
- Rated for commercially produced B100
- Temperature Rated -100˚F to +450˚F
- Max. Working Pressure 3000 psi
- Minimum Burst Pressure 12000 psi

Fuel pressure spring settings 

55-60 psi  silver spring
61-65 psi  gold spring
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.


Product Videos

How To: Riffraff Diesel Fuel Rail Crossover (FRx) (04:01)
How to install the Riffraff Diesel Fuel Rail Crossover (FRx) on your 7.3 powerstroke. Purchase: http://www.riffraffdiesel.com/fuel-rail-crossover-frx/ PDF Instructions: http://www.riffraffdiesel.com/content/RESOURCES/Riffraff_Diesel_FRx_Instructions.pdf
  • How To: Riffra...
    How to install the Riffraff Diesel Fuel Rail Crossover (FRx) o...
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Product Reviews

Showing reviews 1-10 of 162 | Next

  1. Works great 4 Star Review

    Posted by on Nov 22nd 2016

    This my second 7.3 diesel worked great on my first should be good on this one , ball bearing turbo next

  2. Great Mod 5 Star Review

    Posted by on Nov 17th 2016

    Easy install with proper tools. Installed this along with RIFF RAFFS HPO XOVER,BANJO BOLTS and CVD fittings. Also their intake boots. Noticed a 2mpg increase and truck not as clattery as before.

  3. Best Investment 5 Star Review

    Posted by on Nov 14th 2016

    Very noticeable difference in idle. Very clean acceleration through all the gears. Best thing I've done yet that I noticed on the first minute of idling. This is something I will greatly recommend to every 7.3 that comes to my shop.

  4. More MPG, Quieter Engine 5 Star Review

    Posted by on Nov 11th 2016

    One of the best parts I have put on the truck to date. After reading the reviews I was afraid this install would take all day, but I was done in about 2 hours. Just make sure to get the socket and it is an easy job.

  5. PITA 4 Star Review

    Posted by on Nov 11th 2016

    Don't let anyone fool you this is NOT a simple install. It's not the worst I've ever done but I wish I had known exactly what I was getting into. The plug on the passenger side head has no room to work. I found the easiest way was to remover the HPOP. Not a huge deal just one seal and an oily mess to clean up.

  6. Wow; worth the time and investment. 5 Star Review

    Posted by on Nov 2nd 2016

    My E99 with late 99 turbo has 264k. The frx along with the CVD, banjo bolts and hot have made my truck quieter and smoother than ever. It has more power up long grades. I haven't checked mpg yet but I expect to see improvement as well.
    Note: buy the Viton fuel sleeves for the CVD kit from Rifraffdiesel, I didn't and had to pay way more at the Ford dealership. You also will greatly benefit from the square socket they offer for removal in the pipe plugs in the heads. Take out the AC compressor and mount to get to the passenger side plug.

  7. Throttle response 5 Star Review

    Posted by on Nov 1st 2016

    Lil quicker throttle response and much quiter in cab of truck.

  8. Don't hesitate 5 Star Review

    Posted by on Oct 31st 2016

    Easy install helped quiet engine down and
    saves the life of injectors this is a must!

  9. This Was A "No Doubt" Purchase 5 Star Review

    Posted by on Oct 20th 2016

    The FRx prevents a "dead-end" in the fuel-rail, which starves the last injector in each rail of fuel...Especially under load! The included pressure springs are higher quality then OEM.. The fitting that goes to the rear of the engine (driver side) is close to the turbo up-pipe, so I wrapped the fitting with exhaust wrap to shield the heat away.

  10. Simple installation 5 Star Review

    Posted by on Oct 19th 2016

    Fairly easy install. On my engine I removed the check valves from the heads and removed the check valve and drilled out the screen in order to increase the fuel flow.

    Accomplishes the same thing as Driven Diesel's regulated return at a much lower cost.

Showing reviews 1-10 of 162 | Next