FFD Rail System

[lincolnlocker]

Heui injectors need constant pressure at a set volume to perform and the fuel delivery to do the same.

Yes volume declines with a larger hose but pressure builds higher with a smaller hose. Its not like they are drastically changing volume bu adding that plug. But making it easier to supply just enough volume but sustain pressures more easily and consistently.

live life full throttle

 

[KBMKVIII]

I think a simple dyno test would prove/disprove these claims.
One with the rails and one without, no other changes, even a tune.
Monitoring ICP, IPR% and PW etc.
With bigger injectors.
Hell if it works, it works I guess.

 

[Casserly]

Not cost effective but could you imagine the possibility of smaller oil lines feeding each individual injector instead of a hallowed out tube that requires more volume. Id say someone needs to get a set of those heads. Lol. Or make new ones.

Exactly. A stock pump would be able to feed whatever at that point, but I believe only in a race setting unless you put an aftermarket oil cooler on it.

 

[andharri]

So you think that theres no pressure drop in the oil rail?

Just like theres no pressure drop in the fuel rail with huge injectors i suppose?

live life full throttle

Oh no there's certainly a pressure drop. It's just less of pressure drop compared to a smaller diameter region, or design. And it's not really what I think just what the equations say it should be.

Given the length of the system in question (relatively short) and the typical pressures that are witnessed (relatively high ~3000 psi) the difference in a few centimeters of radius change is honestly probably not going to make a huge difference.

However, if you're talking about trends that should benefit performance it would seem this one is going in the opposite direction.

And speaking of pressure drop, the drop will get bigger with less restriction on the outgoing oil (more volume flow Q), ie. larger injectors. The smaller the injector the less pressure drop because the flow (Q) is reduced.

This is why when you place your thumb over the end of a garden hose, the exiting water pressure increases (because the pressure drop inside the hose decreases) and volume output decreases.

 

[andharri]

Heui injectors need constant pressure at a set volume to perform and the fuel delivery to do the same.

Yes volume declines with a larger hose but pressure builds higher with a smaller hose. Its not like they are drastically changing volume bu adding that plug. But making it easier to supply just enough volume but sustain pressures more easily and consistently.

live life full throttle

Agreed, the pressure should be more easily sustainable with less volume to manage.

However, from what I've heard regarding the ability to adequately feed the HEUI injectors the volume of oil is more in demand than the pressure.

Isn't this why hybrid injectors have become so popular and perform so well? I believe there have been numerous threads related to that topic and I don't want to necessarily go down an injector rabbit hole here haha.

EDIT: And again the real question of "volume to manage" in this scenario is the injector oil demand, not the oil log. Reducing the volume of the oil log may relate to more stable pressures in the log, but not where it matters, at the injector. Hooking a garden hose to a fire hydrant will result in more sustainable pressure in the hose, and from the pump, but you won't get more water out of it. Continually increase the hose radius (infinite radius would be no hose at all just open hydrant) and you will get to the point where the hydrant pressure will fluctuate based on the ability of the water company to pump water, but you'll get a heck of a lot of water.

In this case no matter how big you make the hose (oil log) you still have an ultimate restriction at the nozzle (injector). Increase the nozzle (injector) too big and the only fix is more initially supplied volume from the pump.

 

[Magnum PD]

Interesting theory’s.

 

[lincolnlocker]

This is why when you place your thumb over the end of a garden hose, the exiting water pressure increases (because the pressure drop inside the hose decreases) and volume output decreases.

This was my point exactly. Pressure increases. But exactly how much volume out actually is lost?

Ever fill up a bucket with a garden hose and let it fill on its own vs the time it takes to fill with your thumb over the end of it? Its minimal.. and in the case of hydraulic pressure. Its super minimal..

live life full throttle

 

[Jonnydime]

you guys are way over thinking this. If you have a 10 gallon cylinder and that cylinder is full and then you remove 3 gallons you have to replace that 3 gallons to keep the cylinder full. Now take that same cylinder and put a chunk of metal the same volume as 4 gallons into that cylinder you now have a 6 gallon cylinder and if you remove 3 gallons from that cylinder you still have to replace 3 gallons. No more no less and pressure makes no difference since oil is non compressible.

 

[lincolnlocker]

Agreed, the pressure should be more easily sustainable with less volume to manage.



However, from what I've heard regarding the ability to adequately feed the HEUI injectors the volume of oil is more in demand than the pressure.



Isn't this why hybrid injectors have become so popular and perform so well? I believe there have been numerous threads related to that topic and I don't want to necessarily go down an injector rabbit hole here haha.

Yes. But then you have to factor in fuel delivery at the same time. If you can sustain higher oil pressures with less pw for fuel delivery then that makes it easier to inject the fuel volume desired thus making more power to do so.

live life full throttle

 

[lincolnlocker]

you guys are way over thinking this. If you have a 10 gallon cylinder and that cylinder is full and then you remove 3 gallons you have to replace that 3 gallons to keep the cylinder full. Now take that same cylinder and put a chunk of metal the same volume as 4 gallons into that cylinder you now have a 6 gallon cylinder and if you remove 3 gallons from that cylinder you still have to replace 3 gallons. No more no less and pressure makes no difference since oil is non compressible.

No.. you aren't technically removing the oil. Its constant pressure like a dead head effect. Just like fuel.. less space is easier to keep pressure consistent.

live life full throttle

 

[blacksmoke.r.us]

The general equation describing fluid dynamics of this nature is the Hagen-Poiseuille (HP) equation:

dP = 8uLQ/(pi * R^4)

where dP is the pressure difference over the length of the system L, u is the dynamic viscosity (intrinsic to the oil), Q is the volumetric flow rate, and R is the pipe radius.

All injectors require sufficient volume (Q) and pressure (P) of oil to operate. Generally, larger injectors require more volume (Q) than smaller injectors. As can be seen by the HP equation, providing more volume (Q) to the injectors requires EITHER larger dP, smaller L, or larger R.

The pump provides the dP, which drives the volumetric rate (Q), and in practice is the single easiest way to provide more volume of oil, which is why many people opt for aftermarket HPOPs.

While the pump is the easiest thing to replace, the most EFFECTIVE way to increase volumetric flow rate (Q) at a constant supplied pressure (dP) is to INCREASE the radius (R) of the pipes supplying the oil. See that in the HP equation the radius (R) is raised to the 4th power! Small differences here will net drastic differences in the flow characteristics.

In the 7.3l oil supply system the oil log actually represents a larger radius pipe supplying oil to the injectors. In this region of the system the oil will flow the most efficiently and require the least pressure (dP) to move the same amount of volume (Q). Reducing the radius here will not help provide more oil to the injectors, it will further restrict the system.

Reducing that volume will speed up the time it takes to FILL the log with oil, ie. after a complete oil change, but will not provide more oil to the injectors given that the system is already full.

Going with the garden hose and fire hose analogy the question isn't about the volume of the hoses (oil log) but the restriction at the end (injectors). If both hoses have the same size nozzle restriction the larger hose will supply more volume. The only difference will be the time for them both to reach steady state, ie. fill up the hose.

I dont know if this equation is being explained exactly right.

This Hagen-Poiseuille equation is for a constant pipe size diameter. In this case the pipe sizes are changing in the same system.

Also its meant for a constant velocity which in the case of a heui system that is ever changing.

If you increase the radius of the pipe it makes for a larger area. A larger area means more volume. More volume means you need more pump to make up the difference.

If you decrease the total volume needed then you need less pump to meet demand.

Ask youself this if you fill a gallon jug and a 5 gallon bucket which will take longer if the flow rate filling both is the same.

If you incease volume of a given system you need more flow rate to fill it. You can either increase pressure to fill faster or decrease the volume of the system. Thats what these new oil rails do, they decrease the volume of the system needing less pump to meet the demand of the given injector.

If this didnt work the adrenaline wouldnt be able to keep up with the demand of the injectors.

Who knows of a truck that is running 400/300 with a single adrenaline?

This was copied from dieselsite's web page

OUR ADRENALINE PUMP IS DESIGNED FOR USE WITH THE FOLLOWING INJECTOR SIZES:

AA Code Single Shot -94-97 7.3L - stock to 200cc

AB Code Split Shot - Early 99 and California 97 7.3L - stock to 175cc

AD Code Split shot - 99.5-2003 7.3L - stock to 175cc

AC Code Single Shot - T444E and 7.3L aftermarket - stock to 200cc

AD Hybrids - 7.3L aftermarket - up to 285cc

Even dieselsite explains that the pump cant keep up with hybrid injectors larger than 285cc. If the pump supprted more volume they would know.

Also FFD is a great company and wouldn't put their rep on the line to make a little extra dough. These are cheap compared to a pump needed to support high demand systems.

 

[Jonnydime]

But once it's there it's there. When an injector uses a certain amount of oil you only have to replace the oil that was consumed.

 

[Jonnydime]

Ask youself this if you fill a gallon jug and a 5 gallon bucket which will take longer if the flow rate filling both is the same.

But once the 5 gallon jug is full the amount spilled will be the same.

 

[lincolnlocker]

I dont know if this equation is being explained exactly right.

This Hagen-Poiseuille equation is for a constant pipe size diameter. In this case the pipe sizes are changing in the same system.

Also its meant for a constant velocity which in the case of a heui system that is ever changing.

If you increase the radius of the pipe it makes for a larger area. A larger area means more volume. More volume means you need more pump to make up the difference.

If you decrease the total volume needed then you need less pump to meet demand.

Ask youself this if you fill a gallon jug and a 5 gallon bucket which will take longer if the flow rate filling both is the same.

If you incease volume of a given system you need more flow rate to fill it. You can either increase pressure to fill faster or decrease the volume of the system. Thats what these new oil rails do, they decrease the volume of the system needing less pump to meet the demand of the given injector.

If this didnt work the adrenaline wouldnt be able to keep up with the demand of the injectors.

Who knows of a truck that is running 400/300 with a single adrenaline?

This was copied from dieselsite's web page

OUR ADRENALINE PUMP IS DESIGNED FOR USE WITH THE FOLLOWING INJECTOR SIZES:

AA Code Single Shot -94-97 7.3L - stock to 200cc

AB Code Split Shot - Early 99 and California 97 7.3L - stock to 175cc

AD Code Split shot - 99.5-2003 7.3L - stock to 175cc

AC Code Single Shot - T444E and 7.3L aftermarket - stock to 200cc

AD Hybrids - 7.3L aftermarket - up to 285cc

Even dieselsite explains that the pump cant keep up with hybrid injectors larger than 285cc. If the pump supprted more volume they would know.

Also FFD is a great company and wouldn't put their rep on the line to make a little extra dough. These are cheap compared to a pump needed to support high demand systems.

Exactly!

My 170/100 with an adrenaline was completely tapped out to make the power it was making. Made 450hp to the ground. If they are running 400/300s and a adrenaline with these plugs and making max power capable of those injectors, THEN HOLY CHIT BATMAN!!!! That changes the game a bit for the ole dinosaurs!

live life full throttle

 

[andharri]

No.. you aren't technically removing the oil. Its constant pressure like a dead head effect. Just like fuel.. less space is easier to keep pressure consistent.

live life full throttle

Actually, you should be removing the oil. The oil exits out of the injectors when the poppet valve reseats and the fuel pressure returns the pistons to their original positions. Oil volume is constantly being removed.

 

[andharri]

But once the 5 gallon jug is full the amount spilled will be the same.

Exactly, I like your explanation. I was going to repost a similar one but you beat me to it!

 

[lincolnlocker]

Actually, you should be removing the oil. The oil exits out of the injectors when the poppet valve reseats and the fuel pressure returns the pistons to their original positions. Oil volume is constantly being removed.

Only when the injector opens and closes. Its not a open flow scenario though.

live life full throttle

 

[lincolnlocker]

Exactly. A stock pump would be able to feed whatever at that point, but I believe only in a race setting unless you put an aftermarket oil cooler on it.

That would be the cats ass!

live life full throttle

 

[andharri]

I dont know if this equation is being explained exactly right.

This Hagen-Poiseuille equation is for a constant pipe size diameter. In this case the pipe sizes are changing in the same system.

Also its meant for a constant velocity which in the case of a heui system that is ever changing.

If you increase the radius of the pipe it makes for a larger area. A larger area means more volume. More volume means you need more pump to make up the difference.

If you decrease the total volume needed then you need less pump to meet demand.

Ask youself this if you fill a gallon jug and a 5 gallon bucket which will take longer if the flow rate filling both is the same.

If you incease volume of a given system you need more flow rate to fill it. You can either increase pressure to fill faster or decrease the volume of the system. Thats what these new oil rails do, they decrease the volume of the system needing less pump to meet the demand of the given injector.

If this didnt work the adrenaline wouldnt be able to keep up with the demand of the injectors.

Who knows of a truck that is running 400/300 with a single adrenaline?

This was copied from dieselsite's web page

OUR ADRENALINE PUMP IS DESIGNED FOR USE WITH THE FOLLOWING INJECTOR SIZES:

AA Code Single Shot -94-97 7.3L - stock to 200cc

AB Code Split Shot - Early 99 and California 97 7.3L - stock to 175cc

AD Code Split shot - 99.5-2003 7.3L - stock to 175cc

AC Code Single Shot - T444E and 7.3L aftermarket - stock to 200cc

AD Hybrids - 7.3L aftermarket - up to 285cc

Even dieselsite explains that the pump cant keep up with hybrid injectors larger than 285cc. If the pump supprted more volume they would know.

Also FFD is a great company and wouldn't put their rep on the line to make a little extra dough. These are cheap compared to a pump needed to support high demand systems.

You are right that equation is for a steady state system and any real system is dynamic, like the operation of an engine.

However, the ways in which pressure, radius, and volumetric flow rate are related are all described from the general Navier-Stokes relation, from which Hagen-Poiseuille can be derived, and nonetheless exhibit similar tendencies in regards to changes in one affecting the other (the strength of the relationship with radius can vary depending on geometry).

I think FFD does a great job as well, however this particular product just isn't jiving with what I know about fluid dynamics or how the 7.3l oil system operates.

EDIT: "If you increase the radius of the pipe it makes for a larger area. A larger area means more volume. More volume means you need more pump to make up the difference.

If you decrease the total volume needed then you need less pump to meet demand."

This is not necessarily true because the volume that the pump is making up is the volume that is lost through the hose, or flows through it (the volumetric flow rate). The flow rate is really determined in this system by the injector demand, not the pipe or log that feeds it. Therefore, the system volume doesn't matter as much as the flow rate, which is determined by the injectors and the programming.

 

[andharri]

Only when the injector opens and closes. Its not a open flow scenario though.

live life full throttle

Correct, but that is the period in which the interesting things are happening correct? Plunger moves down, volume of oil cavity increases, fuel is pressurized and exits the injector, power is made. Valve closes, plunger moves back into position and oil is expelled so that the process can happen again. That volume change is the flow, or "loss", that the pump is trying to keep up with.

Bigger oil cavity volumes mean more fuel exits or more injection pressure is built, both of which are what we are after for power generation.