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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 196 | Next

  1. This one was a pit of a PITA to install 5 Star Review

    Posted by on Nov 16th 2017

    Took better part of 2 hours to get that darn passenger fitting into the head. Finally discovered that the fitting threads in the head aren't aligned with the other bolts nearby. Also needed to move the A/C compressor over a bit to get some more access. Once I got the fitting alignment thing figured out it was pretty straight forward. By comparison, the driver side fitting was easy to install. This mod, combined with the HPx, did seem to smooth out my idle some. I still need to do the Hutch mod, so it isn't perfect yet.

  2. It is worth it 5 Star Review

    Posted by on Nov 4th 2017

    I did e fuel conversion on my old 97 I used to own. It was a pain in the rear. I was worried when I bought this for my 02 Ex that it was going to be tough as that old truck was. This was so easy and helps the truck a lot. It is such an easy install and does the job well. Riffraff is top notch quality products and shipping. Only thing I don't like is I liked getting the Riffraff decal stickers and I haven't got those in the past few orders. The little badge stickers are okay but those other ones are great. I keep one on my 02 Ex. I like supporting companies that have great products like Riffraff.

  3. Definitely helps with air in fuel 5 Star Review

    Posted by on Oct 29th 2017

    Love this product! Before install had alot of cackle from my 250cc hybrids. After install noticed a smoother idle and top end!

  4. Excellent product 4 Star Review

    Posted by on Sep 19th 2017

    It took me a little longer than others to install but that was my fault. The product overall is well made albeit the instructions don't say much on where to route the lines to avoid chaffing as much as possible. Also the driver side is fairly long, so long that I routed it up and over my intake and turbo rather than under because I couldn't get the line on that way. If you've never heard a rough idle diesel be prepared, the HPx didn't give me any issues but the FRx will make you think the truck is gonna die. If you have a method of putting your truck in a high idle after start I recommend it, doing that cleared out most of my air quickly. After putting nearly a hundred miles on the truck I'm not sure it's any quieter but my idle is much smoother and I no longer have a dead head system.

  5. Great product 5 Star Review

    Posted by on Sep 18th 2017

    It really helped my truck idle a lot smoother. Installation was fairly easy i would highly recommend buying the square socket I rounded one of the plugs and had to use vicegrips

  6. Fuel upgrade 5 Star Review

    Posted by on Sep 17th 2017

    This product was amazing . Quality of product incredible . I have a 2001 excursion and am amazed that ford didn't install this at factory. But thanks Riff Raff for the quality product fast shipment . I tackled this in a day . Took my time no leaks and the truck runs quieter and faster in my opinion. I also purchased banjo bolts,Hpx and increased flow fuel line fittings. Thank you so much

  7. Best regulated system out there! 5 Star Review

    Posted by on Aug 30th 2017

    I had a Strictly Diesel regulated return on my last 7.3L and it worked well. I just put an FRx on my new 02' and while it work just as well, it is so much cleaner to install. Great machine work, and the lines look very quality stainless braided with a nice cover on them. Home run for Riffraff, I recommend this system hands down.

  8. We'll worth the money 5 Star Review

    Posted by on Aug 19th 2017

    Definitely makes a big difference in the way the engine sounds and runs. Lower EGT as well. Every 7.3 should have had this from the factory.

  9. I feel the difference 5 Star Review

    Posted by on Aug 13th 2017

    It made quite a bit of a difference, engine is a lot more quiet, I did the FRx,the High Flow Fuel CVD Fitting Set and the Stainless Steel HPX and removed the needle in the fuel bowl all at the same time and I can A difference in power and fuel economy.

  10. Smoother for sure. 5 Star Review

    Posted by on Jul 30th 2017

    Did the oil crossover and cvd fittings too along with frx line and ww2, and 6pos chip. chip came without program so total results are still out, but definitely better than stock.

Showing reviews 1-10 of 196 | Next