I dont know if this has been covered but i couldnt find anything.

I want to know what you guys think is better, the fuel cross over or a regulated return, for a mildly built 7.3?? I am not looking to make a ton of HP. I DD this truck and tow quite a bit with it so I am building the truck to do just that. I dont really care about dyno numbers, I just want to build a solid combo. I have always liked the idea of the RR with a fuel bowl delete because it is simple and clean but pricey. Now with all the talk of the fuel cross over I am leaning towards that. So I want to know what you guys think??

My plans for the truck are: 38r, stage ones, modded 17*HPOP, fuel system upgrade, and a tranny.

I really would like to know what you guys think so lets hear it.

 

Tag for info.

 

From what you stated as your goals the FRx is all you would really need. With the money you don't spend on the RR you can get the Modded HPOP and a few other goodies. Don't make it any more complicated then it needs to be.

 

So what benefits you will get from a RR vs FRX ?

Is the RR more for higher HP ? From what HP is RR worth installing at ?

 

One of the many questions I have, subscribing.

 

tag info anybody

 

with a rr you can dial up the fuel pressure you want its not a fixed thing. payson said it right if youre only going to stage 1's or maybe even 2's all you should need is the frx. if you go hybrids or higher i would go rr. i have a dieselsite rr in my truck and i love it. its a very nice kit and i like being able to try different fuel pressures to find my liking. either way you will be happy with this kind of mod as they quiet down the truck and make it run smoother. they should have came from the factory with one. other than my bts its the best money i have spent on the rig to date.....

 

If and FRX is installed and at a later time you want to install a RR, will the FRX need to be removed or will it be able to run in conjunction with the RR ?

Thanks

 

Subscribing. Merry Christmas, Happy Holidays to all of you guys(and gals). This 'Brotherhood' has been the best thing I found since I bought my truck. I'm not too good with the computer or the wrench but I love learning more & more. You guys are some of the best, most patient teachers/mentors I've ever seen. This is the best club I've ever joined. Thank You , Thank You , Thank You You know who you are!!!!!!!
There are many on this Foreum

Francis

 

If going from an FRx to R.R., you'll lose the FRx, since it bolts to the fuel regulated port, on the fuel bowl.

 

Both the FRx as well as the Regulated Return accomplish a similar function. They both provide a return path to the tanks from the heads to create a flow of fuel eliminating the dead head issue.

The FRx is a predetermined pressure set at 65-67 psi. A full RR system has a regulator that you can adjust to suit your needs. Neither one of them will be able to add more pressure than the fuel pump will deliver. The RR systems usually replace the supply tubes to the head along with the newly added return lines. The FRx uses the factory supply lines and adds the return circuit.

Installation time and cost for the FRx is much less than a RR system. Like Robin mentioned above the FRx makes more sense for a DD truck, but if you want the flexibility to adjust pressure, a full RR system is the route to go.

The other system to consider is a quad feed set-up. If you get something like an Airdog or a FASS that has a built in regulator. You can feed the heads from all four corners. Since the pump contains the filter and the return flow you can eliminate the factory fuel filter and the return lines from the engine.

All of these will make major improvements to the factory fuel delivery. This will make for a quieter idle and will keep the injectors feed properly.

 

The problem with this question is really in the terminology that has come about in the diesel industry for these products. "Regulated Return" gets thrown around alot, but unfortunately many people have different definitions of what it actually is. Installing a "Regulated Return" really is a misnomer since the stock fuel system actually has a regulated return path stock. Many people get hung up on the fact that the aftermarket "Regulated Return" has easily adjustable fuel pressure and think that is why they need to install one. In reality if all you are after is fuel pressure adjustment that can be had by shimming your stock FPR.

There are two main reasons a "Regulated Return" was created. First was to open up the "dead head" fuel rails and allow a path for the air entrained fuel back to the tank without having to pass through the injectors. Second was to use larger feed lines so that at WOT with larger injectors you would have enough fuel to keep from having a significant pressure drop in the fuel rails. Because of the many different kits they all have little differences so encompassing them under one same isn't really the best either.

So it can be simplified as follows; ending the "dead head" on both stock and high hp trucks is always a good idea, and to see if you need more volume to the heads use a fuel pressure gauge to make the decision, not marketing.

Our FRx was manufactured to cure two things; stock "dead head" fuel rails, and the need to spend a huge amount on something that could be done more simplistically. With this new 2nd Generation FRx we have retained our custom CNC billet fuel cap, but have upgraded that lines with Parker SS Braided lines, and are also including extra springs so you can adjust the fuel pressure where you want it to be. This system will service more than 75% of the enthusiasts in the market while allowing an easy install at a low price point.

If you are going to use large injectors, ~200cc and up, you might need to look into larger feed lines which can be done with or without a "Regulated Return" kit.

The point of this post is to help people not be up-sold on something they don't understand due to incorrect and varying terminology.

 

Also... There are two flavors of FRX out there, one with a simple regulator, and one without. Dino Fuel Alternatives (not sure what other sponsors) sells both:

With Regulator:
Dino Fuel Alternatives | Product Detail

Without Regulator:
Dino Fuel Alternatives | Product Detail

For what it is worth, I run the version without the regulator and performed the FPR mod (costs about 1$) to raise my fuel pressure a bit.

Cheers

 

The full RR also gets rid of all the small steel fuel lines that have been known to break on occasion.

 

With the exception of a fuel cross over (DFA CCK, sadly long before FRx was available), Walbro fuel pump, and Dieselorings FPR billet housing with black regulator spring (KOEO fuel pressure at 73 PSI, never dips below 65 at WOT) my fuel system is essentially stock. With fuel bowl in place and stock fuel feed lines to heads, my 200cc single shots get enough fuel to produce 440+ HP. My goal was 400+ HP and now that I'm there I am leaving well enough. I'm done. Trying to get more fuel flow then I can use or need would be a waste of money for me. Just an example of what can be accomplished without spending big bucks on an adjustable RR so I can dial in the fuel pressure I already have without one.

Edit : As a matter of fact I got to the 440+ HP with the stock FPR housing and a shimmed stock spring.