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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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Part Number:

Product Description

"The Prescription For Your Fuel System Needs®"

We are now shipping our 2nd Generation FRx System that utilizes Parker® 304 Stainless Steel Braided lines. 

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.

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
- 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.

Installation Instructions Click Here 

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Product Reviews

Showing reviews 1-10 of 37 | Next

  1. Good injector insurance

    Posted by Unknown on Jul 15th 2014

    Great product, made a bit of a difference in idle and acceleration seems smoother. Nice to get the air out before it goes through the injectors.

    Thank you riffraff

  2. Great product, Great people

    Posted by Unknown on Jun 28th 2014

    "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."

    This alone is a good reason to buy this, support American workers, and it makes your truck run better in the process!! win win.

  3. Best Mod ever for the7.3

    Posted by tugnutt on Jun 27th 2014

    After installed took it on test run and what a diff. in throttle response. If this also gives the injectors longer life then duh well worth the cash. My 01 has AC so it was easier to unbolt the unit shift it over & install the NPT to the pass. side head...Seems a bit quieter then before..Look forward to loading my camper & going over the pass with plenty of power to spare.

  4. perfect

    Posted by pj on Jun 26th 2014

    No more bogging down of the engine. Smoother idle. Much more quiet, engine has more pick up and idles at a slower rpm. I'm extremely happy with it. I don't think my truck has run so smooth since it came off the line

  5. FRX does what it claims to

    Posted by 12745 on Jun 24th 2014

    The product quieted my 7.3, and I have better pedal response. One of the few products that does what it claims to do. Worth every penny I paid for it. Tight on the install but worth it.

  6. A perfect fit, "USA Made" product

    Posted by ACC on Jun 19th 2014

    Besides a larger exhaust, this is the first mod done to my '02. I decided to install this return system "while I was in there" performing a complete reseal of the oil and fuel systems. It went right in as it should, and the hoses were "clocked" correctly to land on the head fittings perfectly. The recommended middle spring was installed in the regulator. After install, I noticed one thing right away .... quicker starts, especially cold start. It also seems to have a smoother, idle to off idle manner.

  7. Excellent product

    Posted by Eric on Jun 12th 2014

    As usual riffraff came through. Well built product with nice heavy duty hoses. I installed while changing the injectors so I already had most parts out of the way but I would think it would have been an easy install anyway. Between the Hpx, Frx and new injectors from riffraff the truck has never ran better.


    Posted by Ray on Jun 11th 2014

    I was very skeptical that this would do anything, but boy was I surprised it quieted my truck big time while I was driving. Extremely easy to install and very well made. Starts up faster and improved throttle response, I recommend this product for anyone with a 7.3!!!!

  9. Bought to replace leaky stock fpr, got more than bargained for

    Posted by Unknown on Jun 8th 2014

    So I snapped the stock FPR fitting on the fuel bowl and wanted a nicer and permanent solution. Well after I had this installed, not only was the leak obviously stopped, I have picked up a very noticeable amount of throttle response, low end power, smoother running motor. And it looks awesome. Buying the Riff Raff Frx is a no brainer and I recommend to 7.3 super duty owner out there period!

  10. Installed HPx + FRx

    Posted by 2001 f350 cc 4x4 - 29ft 5th wheel on Jun 3rd 2014

    Great quality parts - good directions - much less noise - that`s why i did it
    HPx 1/2 hour install ( easy ) - FPx 6 hours (what a pain) be sure you can remove the plugs first.
    Bought the 9/32 square socket - could not use - no clearance for ratchet or u-joint - used small vice grip and 9/32 ignition wrench (Note to Riffraff)
    Maybe a 1/4 drive rather than 3/8 for the socket

Showing reviews 1-10 of 37 | Next