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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®"

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 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 182 | Next

  1. Great Quality Product 5 Star Review

    Posted by on May 13th 2017

    Not an easy install, but worth the effort. Didn't notice any difference in the noise level when first installed, but after driving for about 30 miles it really quieted down. I ordered the square socket with the kit, but is wasn't helpful on the front plug since there wasn't room for the ratchet and the socket in the small space. Installed this kit along with the Flow Banjo Bolts, Coolant Filtration System, CCV Crankcase Vent Kit, and Stainless Steel HPX, so I think I'm done with mods for a while. The truck is running like a fine-tuned machine now.

  2. Great product 5 Star Review

    Posted by on May 8th 2017

    I highly recommend this product for anyone that has a 7.3L. The product quality is top notch. I installed this along with the Riffraff high flow CVD fittings, and also the Riffraff high flow Banjow bolts. I recommend buying all new sleeves and replacing them while you doing all the new mods to the fuel system. Install was farely simple as long as you follow the directions provided. Overall the truck is running quieter, smoother, and a heck of a lot better thtrottle response. Thank you Riffraff for making another great product to help our engines run a lot better!

  3. Great Quality 5 Star Review

    Posted by on Mar 26th 2017

    I recently installed this on my 99, a little bit of a pain with getting the plugs out but overall not bad. I didn't notice any noise reduction but it did help even out the engine at idle.

  4. Awesome 5 Star Review

    Posted by on Mar 15th 2017

    Awesome product and easy to install. Easier with 2 people to install on the fuel bowl but I did it myself. I like the piece of mind knowing air is not going threw my $1600.00 dollar injectors.

  5. Well made 5 Star Review

    Posted by on Mar 4th 2017

    Follow the instructions and watch the video and you will have no problem with the install. Save time and grief and buy the plug socket. My install was really easy since I was already into other repairs and had the fan, turbo, and pedestal off. Get the HPx also while you're doing this.

  6. Much quieter! 5 Star Review

    Posted by on Feb 27th 2017

    Not a bad install, just takes a little time. So glad I installed it, much faster starting as well.

  7. Mattyhawk 5 Star Review

    Posted by on Feb 27th 2017

    I installed mine with the turbo out doing up pipes and turbo rebuild. I believe in the concept of the FRx, and the evidence on this mod is good, but I did not hear any difference in the sound level of my truck that many mention. Truck runs fine though and glad I did it. No leaks from the first start. Mine looks a bit different than the picture. Hope it holds up over time.

    I wrapped my up pipes and I wrapped the fitting in the rear driver side bank to try and protect it from being so close to the exhaust. Not too much trouble with either freeze plug. My biggest headache was getting enough clearance on the fuel bowl to regulator block with the fuel hard lines there, even with the bowl loosened. I also had to take a huge amount of time to get the plunger seated right as many have warned about. I ended up using an inspection camera from HF to make sure it was seated.

  8. Quiet!!! 5 Star Review

    Posted by on Feb 21st 2017

    Quieted the ol girl right down. Better throttle response!!!

  9. Good Product 5 Star Review

    Posted by on Feb 12th 2017

    I installed the FRx the same time I resealed my plenums and added the billet plenum inserts while I was at it. I did remove the fuel bowl completely it gave me more room on the front passenger side fitting. Do order the small square socket you will need it. The kit comes with a tube of liquid thread seal so you are good to go. FYI the silver spring is for stock setup like mine. For my test drive I seemed to have better acceleration. But I did just install a new turbosmart wastegate with my turbo rebuild (new up pipes, boots, banks power elbo, EVPB delete pedestal) and that really made a difference. I have some other installs like the Riffraff banjo bolts and the CVD fittings. Maybe another day I'm wore out. This project took me about 8 hours (I like to take my time) no lie it is a lot of work but I also resealed my plenum and messed around with improving my wiring system. Seems like when I do one project I see a dozen other things that I need to take care of. Oy Vey!

  10. It really works 5 Star Review

    Posted by on Feb 7th 2017

    I was a bit skeptical at first, but it really works. My injectors seem smoother and quieter now, and it seems to start a little bit quicker too. Very high quality as well

Showing reviews 1-10 of 182 | Next