J&J PERFORMANCE 6.0L POWERSTROKE (2003-2007) REGULATED RETURN:

Saw this and wonder what benefits his would have, and has anybody installed this and can give feedback

Thanks
J. Roach

 

I’m no expert but from my understanding it’s purpose is to ensure all injectors get adequate fuel. There’s an issue with trucks pushing a lot of HP, and therefore fuel, not getting enough fuel to the back injectors causing what’s known as “dead head” these kits provide another avenue to address the issue and get fuel to those back injectors.

I am not aware of this being a problem on stock level trucks only those pushing big HP you’d need bigger injectors and turbos to accomplish.

 

some of warren diesel injectors require this regulated return to be installed, but does give the detail you just gave

 

It doesn't do anything from someone who has actually installed pressure transducers and reading them through an expensive datalogger used in the OE testing world (probably about $35k in today's dollars) into a 7.3 system; it doesn't do a damn thing. Flowing through the heads doesn't change the amount of fuel flowing into the heads.

In fact, the data showed more pressure variation in the fuel rails and had the potential of releasing entrained air within the fuel rails, whereas the Racor-designed system blocks any air from getting into the rails. If you were worried about fuel delivery in the back of the heads, you would add something like CNCFab has designed for the 7.3, feeding into both the front and back. That would not cause the entrained air release.

 

for 6.0 engine..

 

It's the same principle. There is nothing that dramaticly different between the 7.3 and 6.0 delievery system.

 

Jack,
Did any of your testing suggest anything, good or bad, about the check valves in the fuel line banjo bolts at the front of the heads? I've read threads about using the 6.4 banjos until my eyes bled and the consensus always seemed to be that the check valves were the way to go. However, I never see anyone opining as to whether or not they should be replaced as part a maintenance regimen. Any thoughts?

 

I think they should be left in. When you look at the spit-back pressures in the fuel rails, these are pulses from when the injector is closing the intake port on its way to delivering the injection shot. When I set up the data logger and pressure transducers, you could see the pulsation and see it more substantial with the flow-through setup. I played with this over several days, looking at different pressures and configurations. Y2K may remember this from TDS back in 2002 or so. We were all hyper about "Cackle" before Harris was ever known.

Back around ''03-'04, when I was at Nav H for brake testing on their trucks, having lunch with the engineers, we started talking about the 7.3-6.0, and I got into what I was screwing around. The banjos were in both HEUI systems, 7.3 and 6.0. They dropped the damper banjos as soon as they got out of HUEI and went straight through (6.4). If you look at them, they cost extra money and would not have been used if they thought they could get away with less cost. Especially with Ford going hyper on costs in 2002, we saw that in the Ford chassis with '03s. So lots of stuff is missing.

With that testing back then, the rails needed 65psi to counter the pulsing, which is spikes of pressure out of the injectors, and just like a wave pulling back, it's harder to refeed the injector. You want constant pressure with low aeration in the rails. Flowing fuel over rough surfaces or the edges of ports will release entrained air.

I bought all the components and built everything else for a flow-through system on the 7.3. Then I sold it before I ever thought of selling the truck.

I don't have much of the data or images from back then; it was mostly done on my work computer, but I have some traces from the testing, idle pressures, cold and hot, looking for a problem injector, but they all kicked back.


Tube from the back of the driver's head.




One transducer and a means for me to flip circuits around.



My temporary return from the back of the heads



Cold engine data. When I split the heads - the red data is the passenger head with the normal dead headed setup. The back the drivers head flow through. I was using the NGS to shut off individual injectors.





Hot engine data. Calmer when the engine is hot, lower rpm.

 

Thanks for the long version Jack.

Any idea how they overcame the pulsation in the 6.4? Are they running much higher pressures or what?

Any opinion on preventative maintenance of the banjos?

 

The injection is different, and the 6.4L Powerstroke engine uses a Piezo injector.

None that I know of. There are two versions of them, a chage in the retention. I believe some of the early ones came apart, so I believe the changed to a cir-clip. Whatever it was, years ago I replaced one of mine so they both were the newer type. But them coming apart is rare.

 

mine of the reasons I’m skeptic everytime someone says to use a 6.4 part. Just because it fits doesn’t mean its an upgrade, they aren’t the same engine and parts could be different because they needed to be different.

 

On the 6.4 fuel is flowing out of the head back to the fuel filter so there aren't check valves. I believe this is excess fuel that they push thru the injectors not sure of the purpose but most systems these days seem to have them.

High pressure fuel is supplied to the injectors directly from the injection pump via separate high pressure lines, it isn't supplied via the head like the 6.0/7.3.

Edit: The return on piezo injectors is for the "Hydraulic Coupling" that fires the injector. From the 6.7 tech manual: