It's been awhile... I did it back in June and just now had time to write a thread about it. But I guess I can say I have plenty of driving between then and now and I can say it was definitely worth it! The low-end torque I grabbed is pretty sweet. Anyways, here's a few pictures I took. I'll try to add as much info as I can as I go.

Now, to describe the gist of the whole mod and it's purpose... the point of this mod is improve the "dead-end" fuel rail problem that the 7.3L's (I think the 6.0L's have it too) have. In stock form, the fuel will travel through the rails and excess fuel/pressure is bled off out through the bowl... any air that gets in the system gets trapped at the end at the last injector. This reduces power and wears out that last injector prematurely. This mod reroutes the fuel into the back of both heads and out the fronts. The slant of the motor causes the air to travel up the fuel rails and out the other end rather into the injector. The fuel then goes into an external regulator which maintains pressure on the injectors and bleeds the excess off through the return line. Because of this, the stock regulator on the fuel bowl must be capped. With the external regulator, we're able to up the supply pressure a bit. Stock is around 50PSI and I've found that 60PSI seems to be about the sweet spot. Any more and the truck doesn't run any better... if anything, it's a bit worse!

As far as materials go, I would've used 1/4" fuel injection hose all the way, but because of the 6AN fittings on my regulator, the only hose barb fittings I could get were 3/8" so I went with it. It actually worked out since the return line was bigger than 1/4" anyways. I used 1/4" for the supply line to the back of the driver's-side head. The passenger's head is 1/4" solid line so I figured I'd get a more uniform supply if I stuck with those specs. The only fuel line left alone during this mod is the passenger's-side supply line. It goes from the fuel bowl to the back of the head... for some reason, Ford fed the heads from different ends. I don't know why, but it works out because that fitting back there would be nearly impossible to replace without removing the whole up-pipe system. All ports in the block and bowl are 1/8"NPT so that made it easy... here's what fittings I used:

2 ea. - 1/8" NPT to 3/8" Barb (straight fitting)
2 ea. - 1/8" NPT to 1/4" Barb (90* fitting)

I had about 5' of both 1/4" and 3/8" Fuel Injection hose when I did the project... I needed most of it. Just make sure it's injection hose when you get it because the fuel system on the 7.3L is a HIGH-PRESSURE system! Regular supply line will not work!

As far as fittings for the regulator, that's pretty much up to you to solve. I would stick with the hose sizes I used... at first, I was frustrated, but it worked out when it came to the return line. You're just gonna have to figure out what your regulator needs... take it into your auto store and they should be able to help. The cap I used on the stock regulator is a 3/8" NPT... I got it from the hardware store believe it or not. The return line is 5/16", but the nut is larger... I don't know why, but it is!

I think I'm gonna redo all my fittings, though. I don't like how the brass worked out. I'm gonna replace all my fittings with ORB's (O-ring Bosses) and then get some Nineties and Staights like are on my regulator (see pictures) to run to my hose instead. I'm gonna use crimp-on clamps as well... I'll be able to do all that without having to touch the up-pipes! Plus, it'll work much better and look better as well. The rest is up to you... some guys went with all AN fittings and braided lines. I'd like to go hard line, but that'll have to wait until the motor blows and I've got it torn down. Seriously, though... I would go this route if possible because that one fitting in that back is gonna be a PAIN to get in there if you use brass fittings! If you went with an ORB, it'd all go in easily and without having to remove anything. All I had to do was remove the intake hoses and the top of the filter assy. when I did this mod.

MAKE SURE TO USE SOME KIND OF SEALER ON THE THREADS OF ALL FITTINGS... ESPECIALLY THE REGULATOR CAP!!! I USED THE WHITE TAPE STUFF AND THAT HAS WORKED LIKE A CHARM!!!

Now for some pictures... the first few are pretty much self-explanatory... just making the bracket for the regulator. I did have a slight issue with the clearance between the regulator and the fuel bowl. It's kinda a trick to get the filter out, but it can be done.

The area of target:


Here's the back-side of the assy. that was bolted to the manifold... my goal was to make a bracket to sandwich between that assy. and the manifold. See how there's an indention in the manifold and a protrusion on the back of the assy?


Here's the bracket... note the surfaces:




Here it is in place:




Now, for the regulator (thanks to hink10 of FTE for sending this to me free of charge... THANKS MAN!!!)... it looks crooked, but it's not:




The gauge... be sure to use a liquid-filled gauge. This one was about $18... the guy that gave me the regulator told me he had used a regular gauge and the vibrations from the engine destroyed the gauge (I saw it... I took it apart and it was destroyed literally!):


Gauge in place:


Alright, now on to the nitty gritty of the project! This is the front of the passenger's side head. The plug needs to be pulled and a fitting put in place:


Now, I would've used a 90* fitting here, but I couldn't because the barb kept hitting the plenum so, I had to use a straight:


While in there, the port on the fuel bowl where it goes to the front of the driver's head needs to be removed as well as the whole line. A fitting goes in place of it as well:




Now, the fitting on the front of the driver's head needs to come out and be replaced with a fitting as well:


Now, we can start running some hose! On the passenger side, we'll run some hose from the fitting we put in to the left input of the regulator:


Driver's side, prety much the same as the other side:


And the return line: I decided not to cut anything in case I wanted to put it all back. I just pushed the compression nut back on the return line and used the flare like a barb. It did the trick and I have had NO issues with leaks, whatsoever! I just ran it down and around the fuel bowl and then back up again.


Now, this was the worst and I will tell you right off that I intend to redo my fittings eventually. To get this 90* in there, I had to remove on of the bolts on the driver's-side plenum to be able to get it to turn. I also had to unbolt the sleeve on the up-pipe as well. Then I had to cut off a few threads on the fitting so the hose barb would clear the manifold. I've found a straight hose barb went in without having to do anything at all, but the hose hits the manifold so I knew that wouldn't work. But when I got done, this is what I ended up with:


This piece of hose goes back up to the fitting I installed in the side of the fuel bowl.

Now, to finish off the whole freakin' project, a cap for the stock regulator:


Now, just let me know if I left anything out... I'll do my best to answer any questions you might have!

 

Lots of good information. Reps for the writeup and pictures.

These types of posts are excellent learning opportunities for us to learn how things work and the connection/fitting information is extremely helpful.

 

Nice DIY project.

 

2 questions

How long has that gauge been working out? Both of mine broke within a year. One was from ITP and the other from Summit. Not sure why.

What regulator was that? Was it diesel rated?

 

I can't find anything out about the regulator... it was given to me by a guy here on FTE and he had run it for three years (I think) before he gave it to me. There aren't any marks on it, but I think the guy said he got his stuff from Jeggs. As far as the gauge, I've only been running it since June, but it seemed like a nice gauge (it's liquid-filled).

If I have problems, I'll either insulate my regulator, or externally mount my gauge (under the hood and/or in the cab. But I'm loving it... it's funny to watch the pressure, though. It's about 5PSI higher at startup and as the engine and fuel warm up, it'll drop down to 60PSI where I set it at.

Thanks for the comments and Reps, guys!

 

Thanks for all your help jon

 

Just read this thread again and thought I'd mention my gauge is still working perfect... no problems so far! This is a liquid-filled gauge as well...

 

Nice writeup, can't believe I missed this thread, reps when I can....Just tried..

 

Same problem with mine!Leaked all the fluid out of the gauge.Its now pluged waiting for a gauge set up.

Me to Mike! I sent reps for you.

 

Nice job there, I missed the thread before too.

 

Hey Jonathan,

Was just browsing and came across your post. I'm glad the regulator worked out for you. Someone asked what kind of regulator it was. I believe I bought it at Kirban Performance. The only problem was it wasn't tapped for a regulator. I took it apart and drilled and tapped for the regulator. One problem, where I drilled intersected with the bolt hole that connects the top & bottom of the regulator. That caused a leak. After some experimenting, that issue was fixed. I didn't use it that long, I ended up buying a different regulator, think I had a small leak at the regulator and didn't want to mess with it, don't recall. I have pics of what I did in an album.

Anyway, glad you got some use of it, I think it was sitting in my tool box for 3 years, that's what you may have been thinking. Used very little. Good call using rubber line, I used the braided SS line. Looks great, but it's a pain to work with and if a fitting goes, the fix can be a pain too. If anyone wants a parts list for the mod w/ ss braided lines, let me know, I think I still have it. BTW, I have been using a liquid filled regulator for several years and still works perfectly.

Steve

 

Billet Aluminum RACE VERSION - ADJUSTABLE FUEL PRESSURE REGULATOR #5071

Jonathan, what hose, if any, went on the top fitting, of the regulator? btw, killer write-up/pics.

 

Hey, guys... got an update (1.5 years now). About a year ago, I tried to redo the way I ran the fuel line into the rear of the head and it worked up until this month. I ditched the 90* 1/8NPT to 1/4" barb because it hung up on the intake plenums and because I ground a good deal off to get it to clear the collector in the rear. What I did instead was installed a gutted check valve and then bent my own piece of steel and installed it like the other steel lines. It worked ok... kinda close to the collector but hey, let's see how it works. Well, this month it started to leak and I have since had a revelation. I was able to redo a '95 OBS truck and I saw how International ran the left side fuel line into the head. Using two 45* 1/8NPT male to females, it routed the line out of the head and had a decent amount of clearance off of the plenum. It went to a steel line on the OBS, but I figured I could do the same on my truck, just run to a hose barb instead. So, I did and it worked great and it looks a ton better too. I'm still going to go braided stainless and delete the bowl someday but funds won't allow it. Also, on the front right side of the head, I had the same issue, but I could use a straight fitting whereas I couldn't on the rear. Thing is, the hose was almost kinked where I had to bend it to clear the HPOP reservoir. I did the same thing with this port as I did with the rear and again, it worked great. Here are some pictures:

The Rear Before... sucks IMO:


After... MUCH better:


The Front Before... not too bad:


After... like it:


Will also note that the gauge is now giving me issues... not bad for a $17 gauge. The fluid is leaking out and making a mess. Gonna be looking into using a Schrader valve off the OBS fuel bowl I have and see if I can't rigit so that I can install the gauge when I need to tweak the regulator and then monitor the pressure using a gauge in the cab. Anyways, let me know what y'all think. This is how the OBS setups are done and it works great IMO.

 

I had a liquid filled gauge installed too and it leaked all the fluid out also. When that happened, it destroyed the gauge. Mine was from ITP's regulated return kit. I am putting on an aeromotive dry gauge next.

-Drake

 

A dry gauge was what was on my regulator before I got it and the guy who gave it to me said it only took the gauge 3 months to destroy itself. I'm gonna see what fittings it would take to hook the gauge up to a Schrader valve. I'll be sure to post up about it.