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Not terribly hard from what I see
You going to remove the ribbed hose from inside that connects to the module, then run a hose up to a bulkhead in the top hat?

If so that hose will need to have some slack inside the basket I'd think.
 
Discussion starter · #22 ·
You going to remove the ribbed hose from inside that connects to the module, then run a hose up to a bulkhead in the top hat?

If so that hose will need to have some slack inside the basket I'd think.
I have new flex hose comming to replace old one the restriction is in the 90 comming out of the top of the module.
 
Yeah I saw that you found it in the plastic elbow.
I was just thinking it would be easier to replace the entire ribbed hose where it connects to the pump housing inside the basket, than to keep the ribbed hose and try to connect it to a new 90* bulkhead on the top hat.

Sounds like that's what your doing. What kind of connection you going to use for the new flex hose to the pump housing? Still TBD?

I know originally that ribbed hose is like heated and pressed on or something.
 
Discussion starter · #24 ·
Yeah I saw that you found it in the plastic elbow.
I was just thinking it would be easier to replace the entire ribbed hose where it connects to the pump housing inside the basket, than to keep the ribbed hose and try to connect it to a new 90* bulkhead on the top hat.

Sounds like that's what your doing. What kind of connection you going to use for the new flex hose to the pump housing? Still TBD?

I know originally that ribbed hose is like heated and pressed on or something.
I have a couple length 10 mm flex hoses comming and I'm going to use a 6an slip lock fitting to Attach to the an bulkhead and have special epoxy to use with the an sealing washers so there in no leak on bulkhead. The new fuel line quick connect came today and it is .295 I'd vs the stock .220 I'd the stock fitting is. So I'm still waiting on parts.

George
 
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Discussion starter · #26 ·
Discussion starter · #28 ·
OK, I am not sure if the factory hose is conductive. Sometimes they add material in the polymer to ensure grounding.
The pump module has a ground to filter housing I think to disipate static.
 
The mass flow rate is definitely going to be affected by the .22" restriction, but a calculation I did in Solidworks using the standard Bernoulli equations provided a 15psi pressure drop when trying to flow 160GPH of fuel through a 15 foot hose @ .295" (standard 3/8 hose ID). I used plastic wall pipe coeffecient and gasoline fuel density. You would have to command 80psi at the pump, to even see 65psi at the rail (if the equation is correct). Since orifices create pressure differentials and impede mass flow to a degree, you never know if your next restriction lies further down the line. You would have to put a pressure gage before or after the rail. The deadhead fuel system we use, with the measurement pressure sensor at the tank, gets further and further away from accurate, the more we try to push larger quantities of fuel to the injectors. The type of fueling we require, points to 1/2" fuel line all day long as far as volume moved/pressure loss is concerned. Keeping all data the same except for pipe diameter being .391" (1/2" OD), pressure loss is like 2psi.

Pressure loss points to ineffecient pipe size,. It makes the pumps work harder to achieve the pressure wanted at the injector, and we know higher operating pressures decreases pump flow ability!

I've been told by a member that pressure was checked at the rail, and closely resembled pressure read at the stock sensor near the tank. But did they check it while trying to supply 160GPH of fuel? Were they using the factory 3/8" fuel line? Who knows.

Removal of the restriction will definitely help, but let's see if it solves the entire issue.

It takes roughly 71psi, to flow 150 GPH through a .22" orifice, and maintain 65psi on the other side! That's another big loss right at the restriction.

Also, this is based off the pumps flowing a combined 160GPH. They only flow that much at 3 bar, so the actual realistic flow rate at the pressures we need to see, is 150GPH. This puts the pressure drop in my equation to more like ~10psi. Still an issue nonetheless.

Image


Also look at the graph posted on these pumps. Capable of 550hp each on E85 @ .91 BSFC @ 60psi. These things should easily be able to lay down 800whp NO BAP on E. Undersized fuel line perhaps is the main issue? OR the .22" restrictive orifice that reduces pipe ID by 25%?

Another reason why the aux kit is successful. It can supply an additional increased head pressure, to try and overcome the pressure and fluid velocity requirements needed to flow the amount of fuel needed for 800+whp setups on e85 with the stock 3\8 lines.
 
Discussion starter · #31 ·
The mass flow rate is definitely going to be affected by the .22" restriction, but a calculation I did in Solidworks using the standard Bernoulli equations provided a 15psi pressure drop when trying to flow 160GPH of fuel through a 15 foot hose @ .295" (standard 3/8 hose ID). I used plastic wall pipe coeffecient and gasoline fuel density. You would have to command 80psi at the pump, to even see 65psi at the rail (if the equation is correct). Since orifices create pressure differentials and impede mass flow to a degree, you never know if your next restriction lies further down the line. You would have to put a pressure gage before or after the rail. The deadhead fuel system we use, with the measurement pressure sensor at the tank, gets further and further away from accurate, the more we try to push larger quantities of fuel to the injectors. The type of fueling we require, points to 1/2" fuel line all day long as far as volume moved/pressure loss is concerned. Keeping all data the same except for pipe diameter being .391" (1/2" OD), pressure loss is like 2psi.

Pressure loss points to ineffecient pipe size,. It makes the pumps work harder to achieve the pressure wanted at the injector, and we know higher operating pressures decreases pump flow ability!

I've been told by a member that pressure was checked at the rail, and closely resembled pressure read at the stock sensor near the tank. But did they check it while trying to supply 160GPH of fuel? Were they using the factory 3/8" fuel line? Who knows.

Removal of the restriction will definitely help, but let's see if it solves the entire issue.

It takes roughly 71psi, to flow 150 GPH through a .22" orifice, and maintain 65psi on the other side! That's another big loss right at the restriction.

Also, this is based off the pumps flowing a combined 160GPH. They only flow that much at 3 bar, so the actual realistic flow rate at the pressures we need to see, is 150GPH. This puts the pressure drop in my equation to more like ~10psi. Still an issue nonetheless.

Image


Also look at the graph posted on these pumps. Capable of 550hp each on E85 @ .91 BSFC @ 60psi. These things should easily be able to lay down 800whp NO BAP on E. Undersized fuel line perhaps is the main issue? OR the .22" restrictive orifice that reduces pipe ID by 25%?

Another reason why the aux kit is successful. It can supply an additional increased head pressure, to try and overcome the pressure and fluid velocity requirements needed to flow the amount of fuel needed for 800+whp setups on e85 with the stock 3\8 lines.
The factory fuel line is 3/8 od and 5/16 I'd so that's a inherent issue also. I'm going to get rid of the .220 elbow and the nylon quick connect elbow on the factory line and change it to a straight and log from there. To remove just the restriction will be very cheap if they work under $50.00 but you need one specialty tool the nylon line fitting installing tool which I have they are $70 for the installer.

George
 
The mass flow rate is definitely going to be affected by the .22" restriction, but a calculation I did in Solidworks using the standard Bernoulli equations provided a 15psi pressure drop when trying to flow 160GPH of fuel through a 15 foot hose @ .295" (standard 3/8 hose ID). I used plastic wall pipe coeffecient and gasoline fuel density. You would have to command 80psi at the pump, to even see 65psi at the rail (if the equation is correct). Since orifices create pressure differentials and impede mass flow to a degree, you never know if your next restriction lies further down the line. You would have to put a pressure gage before or after the rail. The deadhead fuel system we use, with the measurement pressure sensor at the tank, gets further and further away from accurate, the more we try to push larger quantities of fuel to the injectors. The type of fueling we require, points to 1/2" fuel line all day long as far as volume moved/pressure loss is concerned. Keeping all data the same except for pipe diameter being .391" (1/2" OD), pressure loss is like 2psi.

Pressure loss points to ineffecient pipe size,. It makes the pumps work harder to achieve the pressure wanted at the injector, and we know higher operating pressures decreases pump flow ability!

I've been told by a member that pressure was checked at the rail, and closely resembled pressure read at the stock sensor near the tank. But did they check it while trying to supply 160GPH of fuel? Were they using the factory 3/8" fuel line? Who knows.

Removal of the restriction will definitely help, but let's see if it solves the entire issue.

It takes roughly 71psi, to flow 150 GPH through a .22" orifice, and maintain 65psi on the other side! That's another big loss right at the restriction.

Also, this is based off the pumps flowing a combined 160GPH. They only flow that much at 3 bar, so the actual realistic flow rate at the pressures we need to see, is 150GPH. This puts the pressure drop in my equation to more like ~10psi. Still an issue nonetheless.

Also look at the graph posted on these pumps. Capable of 550hp each on E85 @ .91 BSFC @ 60psi. These things should easily be able to lay down 800whp NO BAP on E. Undersized fuel line perhaps is the main issue? OR the .22" restrictive orifice that reduces pipe ID by 25%?

Another reason why the aux kit is successful. It can supply an additional increased head pressure, to try and overcome the pressure and fluid velocity requirements needed to flow the amount of fuel needed for 800+whp setups on e85 with the stock 3\8 lines.
So I used to be a paper engineer in school, and then when I got a job, I had to be hands on and test everything. :) I can tell you that the pressure recorded at the rear of the system by the factory pressure sensor will match a sensor put on the rail about dead nuts, even at really high flow rates. I've checked it before when somebody wanted to claim the system didn't work right and the sensor had to be relocated. I'd have to hunt for the logs, but I've done the fact checking. Simulations are great, but empirical evidence is better IMO.
 
So I used to be a paper engineer in school, and then when I got a job, I had to be hands on and test everything. :) I can tell you that the pressure recorded at the rear of the system by the factory pressure sensor will match a sensor put on the rail about dead nuts, even at really high flow rates. I've checked it before when somebody wanted to claim the system didn't work right and the sensor had to be relocated. I'd have to hunt for the logs, but I've done the fact checking. Simulations are great, but empirical evidence is better IMO.
I agree entirely that actual testing > calculations because of the many variables. I know its not 100% accurate, and I hope no one takes it as gospel.

Your situation could be entirely true, but up to a certain flow rate. That's a law of fluid physics.

How much fuel was the engine receiving during the logs? Were you using the aux pump? Is the aux pump spliced in after the factory sensor?

These are large variables in the equations. The OP isn't using an additional aux pump that can supplement increased volume, creating increased fluid velocity at a convergence area. In my simulations a T would create a pressure spike that would equalize eventually. This spike at the area of convergence could be higher for instance, but line pressures before and after a few feet are normalizing.

Also there are things that are pretty accurate like the fluid velocity required to move 150GPH through a straight 3/8 hose (no kinks), at any given pressure. Currently, 150GPH creates a very turbulent flow and just based off 'paper engineering' is WAY beyond ideal. That is not refutable, and there can be substantial negative effects from that. Like pressure loss, and increased heat from friction.

Will it work? YES
Will it be at the highest effeciency? Just based of fluid velocity, NO.

How much less effecient is a 3/8 line to a 1/2 line @ 150GPH @ 60-65psi? That would require back to back testing and could be proven to be too little to be financially worth it. Now add two aux pumps to a stock system, effeciency decreases more again.
 
I'm not debating the fact that the elbow is a restriction. The fact that the pressure sensor is well after the elbow though means the two don't really have an interaction.

On the car I tested, it had an aux pump and 85% ethanol making about 750whp. That's about 87g/s worth of fuel flow which is around 400L/h.

So now, at the end of the day, what everyone wants to know is: so what? How does somebody fix it and what happens if they don't?

FWIW, I worked for seven years at an engineering firm that designs HRSGs, and we had to guarantee certain flow rates and heat conversion or we'd pay penalties in the millions of dollars, so I can appreciate the world of CFD and running numbers.
 
I'm not debating the fact that the elbow is a restriction. The fact that the pressure sensor is well after the elbow though means the two don't really have an interaction.

On the car I tested, it had an aux pump and 85% ethanol making about 750whp. That's about 87g/s worth of fuel flow which is around 400L/h.

So now, at the end of the day, what everyone wants to know is: so what? How does somebody fix it and what happens if they don't?

FWIW, I worked for seven years at an engineering firm that designs HRSGs, and we had to guarantee certain flow rates and heat conversion or we'd pay penalties in the millions of dollars, so I can appreciate the world of CFD and running numbers.
Duplicate.
 
I'm not debating the fact that the elbow is a restriction. The fact that the pressure sensor is well after the elbow though means the two don't really have an interaction.

On the car I tested, it had an aux pump and 85% ethanol making about 750whp. That's about 87g/s worth of fuel flow which is around 400L/h.

So now, at the end of the day, what everyone wants to know is: so what? How does somebody fix it and what happens if they don't?

FWIW, I worked for seven years at an engineering firm that designs HRSGs, and we had to guarantee certain flow rates and heat conversion or we'd pay penalties in the millions of dollars, so I can appreciate the world of CFD and running numbers.
At the pressure we need, the AEM pumps are rated for about 285 lph each. I know both in parallel is not 'double the lph' but would have to plotted on an effeciency curve to find combined head/flow. Too many variables.

Since the OP is trying to reach the maximum of what the AEM pumps are rated for, he can't have any loss of effeciency in the system. Just looking at the supplied graph on the pumps VERSUS what people are experiencing, tells me something is hindering their performance even at @18 volts!

It very well could be just the elbow restriction at this point, and partially the hose id. That's where this testing he's doing will be a really good thing for him to provide the real world analysis.

The restriction being before the pressure sensor means that the pressure across the pump outlet is higher than what's on the other side. Like I said above, through a .22" orifice could be a 6psi loss. The sensor wants to see 65psi, but the pumps have to produce 71psi to achieve that through the elbow. This could account for a big flow inhibitor because your pumps are working at increased pressure, thus lower flow capability. 6psi difference on just one of these pumps is worth 15-20lph.
 
What is the supply voltage at 100% duty cycle while running in the car?


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Sorry Karch, can you elaborate on this? I think we would need owners using these pumps (that see pressure drop offs), to chime in and explain what they're seeing.

I would highly doubt those pumps are actually doing 285L/h a piece at 5 bar given the results people have had. Personally, I think they just aren't capable of what they're claimed to be.
If after the obvious flow inhibiting restrictions are removed, then the true capabilities are going to be exposed.

You're probably right on about the specs. The testing done is lab environment and uses best case scenarios. It doesn't use a 20' long fuel hose with necks, kinks, and restrictive orifices in its way either!
 
I was told the supply voltage to our stock pumps at full demand is 12.8VDC, due to the FSCM (or whatever it's called), whereas I think the AEM pumps are rated at 13.5VDC.

The output, as you know, increases significantly as you increase the voltage, so it would make sense that the AEM pump output would be less than advertised if the supply voltage wasn't as high as what they are using for their tests.
 
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