Bosch 044 External Pump Setup.

[Gts-t]

Cant be as noisy as this, has got me thinking about doing something like ben. Lucky its not my daily or it would have to go

[salival]

Only have pics of the tank etc setup under the car.

The relays and wires are not that interesting

5 relays and a lot of wiring.. will be annoying if I can't use it..

WOW that tank looks hot, I wonder who made that

[GTR-Ben]

Some welder made it, looks like the muppet above

I am going to try a different method with a high current voltage control system. Which Jay Car do a kit for also.

Really like the idea of controlling the output of the pump and I am not giving up!

[femno]

Good idea and all, but theres too many bits that can go wrong...

If the unit fails (which seems complex) then BANG engine bye bye.

Keep it simple i rkn.

If you cant handle the noise dont drive a car that makes alot of power!

[GeeTR]

I am going to try a different method with a high current voltage control system. Which Jay Car do a kit for also.

I think they do a 12v, 20amp PWM kit, maybe the square wave would kick the 044 over?

If the unit fails (which seems complex) then BANG engine bye bye.

Yah, I reckon this is all too risky imo to try on my car without a closed loop failsafe as per a comment I made over 13 months ago. Even a voltage switch that kills the CAS if boost goes over 2psi with f.pump input lower then 13v should work.

Interesting thread

Edited June 6, 2008 by GeeTR

[Sydneykid]

I see no logic in having an over the top fuel system in the rare chance that one of the components might fail suddenly without notice, without any indication, just stop pumping. Manufacturers realise how import fuel is, that's why the failure rate on fuel pumps is miniscule, tiny, almost non existent. If you're that paranoid how about you watch the knock warning light on the dash if you have a Power FC, or wire in a fuel pressure sensor if you have a Motec, Autronic or any number of high end ECU's that have that facility, or if you don't have any of those ECU's how about you buy a fuel pressure gauge and bother to look at it. The high end gauges (GReddy for example) also have an adjustable warning light for low fuel pressure that is so bright surely you can't ignore it.

I'm actually beginning to think it's really for bragging rights, "my car has a bigger fuel refinery in the boot than yours" or "my car has so many fuel pumps I need a bigger stereo".

Cheers

Gary

[Guilt-Toy]

hahahaa sydneykid! love it.

fuel refinery. I have had my walbro pump suppy fuel directly to a 044 external and it works fine for me.

[GTR-Ben]

No idea what your on about there Syndeykid, and I feel quite offended you would accuse me of doing this for bragging rights. Either that or you did not read my whole thread (which is a common thing for people making stupid replys).

No idea what wanting to control my fuel pump has to do with looking at a fuel pressure gauge..

The way the system is also wired means that if a relay or one of the control systems happens to fail.. the pump stops.

R32 GTR's came out factory with the system.. you think Nissan would bring out something bad in a $100,000 car.

I asked a long time ago many questions about voltage control systems. As per any forum people are always quick to post up dribble on things they read in another post but when it comes to a question about something that might take some thinking or expertise.. there is nothing.

My fuel system is not "over the top" it's a simple lift pump with a surge tank and external pump, I just want a simple system to control the pumps output varying on AFM or similar input.

If I listened to every negative person telling me what I can't do with this kind of thing.. I wouldn't even have built my car..

Many industries have pumps that they need to control the output on, pulsing voltage to the pump should slow it down for the same current input, lowering flow and noise.

Thanks for people's 2c about why you think it's bad or telling me how your system works.. but unless you have some knowledge in pumps, voltage etc.. then you're not really helping. There are literally 1000 threads on putting a bigger wires to your pump and letting it scream..

Edited June 6, 2008 by GTR-Ben

[Sydneykid]

No idea what your on about there Syndeykid, and I feel quite offended you would accuse me of doing this for bragging rights. Either that or you did not read my whole thread (which is a common thing for people making stupid replys).

No idea what wanting to control my fuel pump has to do with looking at a fuel pressure gauge..

The way the system is also wired means that if a relay or one of the control systems happens to fail.. the pump stops.

R32 GTR's came out factory with the system.. you think Nissan would bring out something bad in a $100,000 car.

I asked a long time ago many questions about voltage control systems. As per any forum people are always quick to post up dribble on things they read in another post but when it comes to a question about something that might take some thinking or expertise.. there is nothing.

My fuel system is not "over the top" it's a simple lift pump with a surge tank and external pump, I just want a simple system to control the pumps output varying on AFM or similar input.

If I listened to every negative person telling me what I can't do with this kind of thing.. I wouldn't even have built my car..

Many industries have pumps that they need to control the output on, pulsing voltage to the pump should slow it down for the same current input, lowering flow and noise.

Thanks for people's 2c about why you think it's bad or telling me how your system works.. but unless you have some knowledge in pumps, voltage etc.. then you're not really helping. There are literally 1000 threads on putting a bigger wires to your pump and letting it scream..

Wooooo, settle.......I wasn't pinking on you, you don't have a refinery in the boot.

I actually like your electical concept, but I see a couple of things I would look at;

1. The circuit drawing doesn't show how you have the in tank pump driven electrically, if you have alrewqady done it, I would also drop the voltage to the intank pump, no use filling up the surge tank over and over with the same fuel if the main pump isn't using all of it.

2. I would check the voltage at the low voltage relay when both pumps are running, it may drop below the threshold required to hold the relay open

3. Also I would check the voltage at the high voltage relay when the pumps are running for the same reason.

A few minutes with the multimeter shoud reveal all.

Cheers

Gary

[GTR-Ben]

Thanks, had a feeling you were just making general comments.

I genuinely want this setup to work, just a personal mission

I don't have the lift pump voltage being controlled currently. It's a standard GTR pump, with small wiring, supplying the surge tank. Not as worried about that pump pumping fuel but I can see what your getting at.

Looking at it now, I think changing the voltage is the wrong way to go about this due to current changes etc.

If a high current motor speed controller can achive what I would like to do with "fixed-frequency pulse-width-modulation" then that would be great. The pump could then ramp up to speed with load.

The current does not change so thats cool.

Any thoughts.

also.. how come the standard GTR pump which is just a bosch in tank pump.. that still flows a ton of fuel can run via the control module at 7 and 9V.. yet this one can't?

Edited June 6, 2008 by GTR-Ben

[GTR-Ben]

http://www.siliconchip.com.au/cms/A_110145/article.html

Thats the one.

[GTR-Ben]

No Jaycars carry the KC-5465

The NZ and AU sites both do not list it also but it's in the new catalogue..

Anyone have a jaycar close by in Aus?

[GeeTR]

Got one 20mins away.... Fyshwick

Store locater

Edited June 7, 2008 by GeeTR

[GTR-Ben]

I am heading over to Sydney in a couple of weeks so might have a look then for the kit.

No one has them here..

[Ryan1200]

Another product to consider: http://www.weldonracing.com/product.phtml?...Pump_Controller

[MBS206]

I can't quite understand what you're getting at with a current increase in lowering the voltage... If you do that, you'd be breaking the laws of electricity!

The fuel pump is affectively an electric motor.

Once the pump is up at speed, you have basically 0 amps flowing (Due to a back EMF)

When you just slam 12V straight to the pump, the moment you hit it with 12V, is when you actually get your largest amount of current flowing. As the motor winds up, resistance inside it increases affectively (It really doesn't, but the back EMF acts as a resistance) causing the current to drop off. (It's more complicated then that, but, that is affectively how it works in simpleton rules)

When you put 12V on this pump, you get approximately 12V back EMF (12 volts attempting to flow the backward direction) if there's no load. Apply a small load, and the back EMF drops. So you'll have a couple of volts across the pump.

If you put 7 Volts on the pump, you'll get approximately 7Volts back emf, or a few less volts when loaded.

Now, seeing as the resistance of the pump really does stay the same. Pretending the pump has a 1Ohm resistance, at 12Volts, you have 12amps flowing... Now drop your voltage to 7Volts, and all of a sudden you have 7amps... Notice how the current has dropped as the voltage drops?

Hence, you don't have an "increase in current" from everything that I can pick up from this setup. If you did... I'd be worried, as your current is dictated by the resistance, and the voltage... Increase resistance, current drops. Decrease voltage, current drops... In this system, for comparing the 7VS12 volts, the resistance can be quoted as constant.

Lastly, noise...

The Bosch 044 is NOT a noisy pump when mounted correctly. It's all about removing vibration...

I have mine mounted in tank. The pump is completely isolated from touching everything else with rubber. Including the inlet and outlet, which have rubber hoses on them...

The intank setup posted earlier, had a nice rubber mount for the pump, but, it's issue was the nice solid metal joint, going to the surge tank... All the vibration just transmit through that...

The only time I can hear my 044 is when the car nearly stalls (Churning over at 300 - 400RPM) as the exhaust noise goes to basically NOTHING. And only then, is it a slight whine that I can hear...

Either that or stand beside the rear wheel on drivers side, and there's a slight noise too... That's it...

No need to slow it down, I run mine at full battery voltage 24/7

[GTR-Ben]

Thanks, that why I was asking.

A lot of people say "oh no but the voltage will increase a LOT!" but no one explains why.. And I am no electrical expert.. just people pretend to be on the internet and misguide you.

With a closed loop system thats keeping the motor at a constant RPM, a decrease in supply voltage will cause an increase in current by the laws of power conservation.

I had originally though just that, as the pumps voltage is lowered, the current draw would also be less because the pump is now going slower..

Surly if there was a current problem they would not use it with factory systems.

About the noise.. driving it today with it mounted under the car (pump is rubber mounted and so is the tank) I can not hear it at 12V while the car is running. There is a hum from outside the car but it's not a lot. It just seemed simple and it was something I wanted to wire up...

Not only for noise but also to lessen the amount of fuel I was heating up was a reason for doing this.

I have the whole system ready to go, the pump just doesn't like lower voltage..

So leaving my setup how it is.. I guess the 044 just can't push the fuel with only the current 7v supply.

[MBS206]

Another idea might be, instead of returning the fuel from the fuel rail to the surge tank... Return it to the actual fuel tank.

As to the conservation of power. WTF?

I've never heard of "the conservation of power"

Power, in an electrical sense is purely dictated by P=VI, that is, Power, in watts, is equal to Volts, times by Amps.

And your voltage is given as V = IR, that is, voltage, is equal to amps, multiplied by resistance in ohms.

The ONLY reason I can see it being an issue, is that the voltage is generally dropped from 12volts, down to 7, via an inline resistor...

Hence, your total current flow is limited, and it might not be enough to start the pump at 7volts...

I'll go back over your diagram and see what the go is...

Edit: Can you draw me up a full wiring diagram of how you have this? Your first diagram is abit ambiguous.

Also, you say the pump primed, and then stopped... Have you attempted to START the car?

Not sure if you realised, when you first click to "On" the car will only flick the fuel pump on for 3 seconds I beleive it is, at which point, it shuts off again until you start to get the engine cranking...

Edited June 8, 2008 by MBS206

[GTR-Ben]

I prefer to have the rail returning to the surge tank at present. I only run braided lines from surge tank to rail. If I ran it from rail to tank I would need to weld more fittings etc. Not hard but no need.

Conservation of power is probably the wrong way of wording it.. and not a "technical" term.

The pressure in the fuel system is governed by the regulator, so we can consider this fixed. So for a certain flow the pump motor needs to output a certain amount of power.

For this power to remain constant with a drop in voltage (keeping the flow the same, as I was incorrectly thinking) the current would have to go up.

Obviously as there is no feedback system to keep the pump operating at a constant RPM, it naturally slows down so the current ofcourse does not increase.

The parts missing from that diagram are just the earths for the relays, the source of power to the voltage switch and control module. What would you like to see?

The voltage is dropped by a voltage divider so not as simple as an inline resistor.

Yes I don't think at 7V it has enough current to turn the 044 trying to push against 50psi rail pressure. Thats with the car off.. I didn't try and start it.. so maybe when the rail pressure goes to 40 or so and the voltage gets a little higher it would work. It did some strange things though when it was at 7V.

A. It held the rail at 50 psi, but the pump was only making small sounds.. not a running noise.

B. When I turned the key off it continued to make these sounds until i unplugged the power to the relay (I guess it was holding the relay closed somehow)

The External pump was wired to a ignition switched power also, so it would not turn off after a few seconds like the stock pump.

Edited June 8, 2008 by GTR-Ben

[MBS206]

Do you have diodes sitting across your coils on the relays? (Or indication LEDS on the coils)?

These remove a spike which can cause the relay to hold on for a while, and cause you other issues.

The thing with the fuel pressure... If you slow your pump, you WILL get a drop flow from the fuel pump, at which point, 50PSi will still be made, but less fuel will flow. Eventually as you slow the pump though, you will loose rail pressure.

Just because your rail is setup to have "50PSi" does not 100% mean you'll have 50PSi, it just means the max, at that vacuum point you'll have, is 50PSi...

So as you lower your voltage, you can have fuel pressure drop, and you will 100% guaranteed have a fuel flow drop.

If it worked how you were saying, I'm sure HEAPS of companies would only run at 6volts or so...

Your current, is PURELY dictated by V = IR... Keep resistance constant, and your current follows the voltage change. (Volts up, Current up, volts go down, current goes down)

The only thing I can think of, is to put a diode in line on each relay...

So you'd put 2 diodes in your system... Will help isolate the 2 relays that are triggered from the AFM. May help remove that strange problem you said you had when you switched it off.

I'd also be checking what actual voltage you have across the fuel pump when in 7V mark.

From what I understand of the the GTR fuel slowing thing, is that it uses a voltage divide, which places a resistor in line also... It's how they work... (not explained properly by me there, but yeah... It divides the voltage by wacking a resistor in line from what i know of the workings of the GTR fuel slower)

The only other thing I could think for you to do...

Put another fuel pump inline with the 044.

You'll need 2 one way check valves.

But run another GTR pump in parallel to the 044. And when the voltage goes above 2.5Volts, turn the 044 pump on. When it drops below. Turn it off. Run the second GTR pump full time. The one way check valves will stop fuel attempting to flow backwards through the 044 when it is turned off. And the second one way check valve after the GTR pump, will stop fuel flowing through the GTR pump when the 044 pump is on...

|FUEL TANK|------|GTR LIFT PUMP|---|Surge tank|---GTRPUMP---CHECKVALVE---\_______Engine fuel rail...

-----------------------------------|Surge tank|---044PUMP ----CHECKVALVE---/

My attempted drawing of how to set them up...

Edited June 8, 2008 by MBS206