Bosch 044 ..This explains a lot
Discussion
I was just on a website looking at the Bosch 044 and this is there description and recommendations for installation..
Description
"This is the popular Bosch Motorsports "044" fuel pump. These are inline Bosch competition fuel pumps, and it is generally recommend they be installed between the factory (or another aftermarket) in-tank fuel pump, and the fuel rail."
It seems that they are designed to be fed at pressure ( in series ) by another pump ... i would have installed a two pump system along time ago if i had known...:/
Description
"This is the popular Bosch Motorsports "044" fuel pump. These are inline Bosch competition fuel pumps, and it is generally recommend they be installed between the factory (or another aftermarket) in-tank fuel pump, and the fuel rail."
It seems that they are designed to be fed at pressure ( in series ) by another pump ... i would have installed a two pump system along time ago if i had known...:/
Can't see the point of a swirl pot on a road car.
Any problems that have existed are to do with the stock tank, outlet pipework & wiring. Sort those & the issue of a noisy 044 goes away & it is good for upto 550 bhp proven without any issues for road & trackday use.
The 044 pump is noisy either because it's starved of fuel or hot fuel which is vaporising.
Any problems that have existed are to do with the stock tank, outlet pipework & wiring. Sort those & the issue of a noisy 044 goes away & it is good for upto 550 bhp proven without any issues for road & trackday use.
The 044 pump is noisy either because it's starved of fuel or hot fuel which is vaporising.
GTO600 said:
Can't see the point of a swirl pot on a road car.
Any problems that have existed are to do with the stock tank, outlet pipework & wiring. Sort those & the issue of a noisy 044 goes away & it is good for upto 550 bhp proven without any issues for road & trackday use.
The 044 pump is noisy either because it's starved of fuel or hot fuel which is vaporising.
+1 common culprit is a claggy fuel filter . I now replace mine annually , if not more frequently, and the pump remains quiet.Any problems that have existed are to do with the stock tank, outlet pipework & wiring. Sort those & the issue of a noisy 044 goes away & it is good for upto 550 bhp proven without any issues for road & trackday use.
The 044 pump is noisy either because it's starved of fuel or hot fuel which is vaporising.
Hi Kevin, the swirl pot is for the track.. very twisty track at that....the pump only gets noisy when fuel is low..but really i want the swirl pot so that heavy cornering can be done on low fuel with safety...as i will have combine heavily baffled tank with pressurized swirl pot it should be a pretty sorted fuel delivery system...giving the 044 a helping hand with pressurized feed to combat noise on low fuel is a bonus.
Simon...how did you pressurize your fuel tank?...i have ordered a 7psi lifter pump and a 5psi regulator on the swirl pot return which equates to about 0.3 bar positive pressure...how does pressurizing the tank work with the newton inline breather?....it has +- 0.05 bar postive limit and a 0.0055 bar negative limit, so it is designed to keep it stabilized with normal air pressure.
I think knowing what i know now about the bosch 044 i definately would add a smaller pump to feed it...in fact when anybody does the pump upgrade i think it is a good idea to retain the stock pump to feed to 044....hmmmm...i wonder what NM did with all my stock pumps over the years :/
Simon...how did you pressurize your fuel tank?...i have ordered a 7psi lifter pump and a 5psi regulator on the swirl pot return which equates to about 0.3 bar positive pressure...how does pressurizing the tank work with the newton inline breather?....it has +- 0.05 bar postive limit and a 0.0055 bar negative limit, so it is designed to keep it stabilized with normal air pressure.
I think knowing what i know now about the bosch 044 i definately would add a smaller pump to feed it...in fact when anybody does the pump upgrade i think it is a good idea to retain the stock pump to feed to 044....hmmmm...i wonder what NM did with all my stock pumps over the years :/
"This is the popular Bosch Motorsports "044" fuel pump. These are inline Bosch competition fuel pumps, and it is generally recommend they be installed between the factory (or another aftermarket) in-tank fuel pump, and the fuel rail."
that is how mine is plumbed in - I run 2 fuel pumps
a single 044 pump should be adequate for over 700 hp if plumbed in this way
that is how mine is plumbed in - I run 2 fuel pumps
a single 044 pump should be adequate for over 700 hp if plumbed in this way
Gadgeroonie said:
"This is the popular Bosch Motorsports "044" fuel pump. These are inline Bosch competition fuel pumps, and it is generally recommend they be installed between the factory (or another aftermarket) in-tank fuel pump, and the fuel rail."
that is how mine is plumbed in - I run 2 fuel pumps
a single 044 pump should be adequate for over 700 hp if plumbed in this way
that is how mine is plumbed in - I run 2 fuel pumps
a single 044 pump should be adequate for over 700 hp if plumbed in this way
..fair do to you Mike, you told me to put two fuel pumps along time ago, one feeding the other, i should have listened, i thought you were advising it as a upgrade for when i was going to go for Gt28RS, i didnt realise a bosch 044 is always meant to be fed by another pump..Edited by R0162 on Thursday 22 March 21:56
TuxMan said:
I'm with Hans on this one , if the first pump will only shift 100LItres per hour and the second needs 200 liters per hour at WOT how is the first pump going to supply that volume ?? Tux
because the pumps are performing at totally different pressures... the first one isnt being asked to provide pressure thus it flows more.I've not done the maths, but I suspect the stock pump can flow more fuel at 1bar than an 044 can at 4.4bar.
Volume does depend on pressure a bosch 044 can flow 260 ltr/hr at 3 bar but reduces to 200ltr/hr at 5 bar, that is when fed by another pump, when fed at atmospheric pressure they are rated at 200 ltr/hr @ 3 bar, big difference.
As Adrain stated atmospheric pressure is 1 bar, so by definition fuel pressure is 1 bar, but when we are talking about pressurizing we are talking about putting an aditional positive pressure in relation to atmospheric pressure.
This is the starting point, if you fill a tank with 1ft deep of fuel and put a hose to the outlet pointing staright up, the fuel would rise 1ft up the tube, to pressurize the tank above atmospheric, this would push the fuel much higher up the tube...
Flow does not matter so much with a swirl pot because the fuel gets returned to the pot, and as pressure increases with boost and less fuel gets returned and more fuel gets burned, the lifter pump will need to keep up..... but basically nobody stays on full throttle all the time, so the lifter pump and volume on swirl pot and return from regulator means the swirl pot always stays in front.
So i have a low pressure lifter which flows 165 ltr/hr and a 044 which flows 260 ltr/hr...this is ok for a swirl pot due to the design and the way a car is driven.
But when two pumps are inline, one pump feeding another.. i assume they have to flow the same..but like Andy says when a pump does not need to create 4 bar pressure it will flow more....a stand alone 044 at 4 bar when you put your foot down only flows 180ltrs/hour, if you have high boost 1.5 bar then the flow drops even more and so on... so seen as though the most critical time is when you are on the power and the fact that the flow reduces with pressure...then the feed pump finds it easy to keep up...so although a m400 pump flows less at 3 bar it may flow more at 0.5 bar to what the 044 needs....
but as you can tell this is all guesstimates and talking theoretically...i think when linking the feed pump to the 044...the different fuel flows at different pressures need to be thought through.....to make sure the 044 is not going to be restricted by the feed pump..because if it is going to be restrictive then you are better running straight from the tank at atmospheric at least then you are sure of 200ltr/hr at 3 bar....
I am beginning to wonder if my 165ltr/hr lifter pump is enough...i would appreciate if somebody could follow me on this line of thought because it is not scientifical..this is all about working the flow in relation to fuel used this way i can work out the amount of fuel getting returned and add that to my lifter pump...
When i did some rough guesstimates it was based on the 044 flowing 200 ltr/hr...but i didnt take into account that by feeding the 044 at pressure its flow has just increased to 260 ltr/hr at 3 bar ....
... but at least at 4 bar when i have my foot down that flow will be reduced to 230 ltr/hr... and the lifter is 165 ltr/hr at 7psi, i assume it will flow a bit more at 5psi...plus the returned fuel from the 044 will be getting added to that flow.
So with a swirl pot the critical part of this is return flow from the 044, I do not know the real maths so i have to just do some like for like comparisons...and first i think .."is there any way my car can use 260 ltr/hr?"... thats nearly 5 full tanks in 1 hour...i am thinking not....
So lets err on the safe side and say 6mpg going full whack around top gear track, thats 50 litres per 100km - 0.5 litre per km, thats 1.5 litre for every lap as the track is 3km long.
Lets err on the safe side even further and say 2 litre per lap, thats 1 min 20 per lap, so a full tank gets 30 laps...i think i am way safe on that..so a full tank lasts 40 minutes...thats 60 litres in 40 minutes...so lets say 90 ltr/hr fuel used.... so if the 044 is flowing 230 ltr/hr at 4 bar..then it would stand to reason that 140 ltr/hr gets returned??...
( on a side note.....With understanding the amount of fuel getting returned and constantly recirculated it is easy to understand why the fuel can get heated from underhood temps and local coolant pipes.... and I am better understanding why it had such an effect on performance when i reduced underhood temps and heat insulated the fuel return pipe, tank and the fuel lines.
When i say affect on performance... my power loss on scorching hot days used to be noticeable.. i used put it all down to air intake temps and IC...but soon discovered hot expanded fuel was playing just as big part in power loss)
I think i am well covered with the lifter and swirl pot system but we need Justin to come along and do the maths with having two pumps inline, as without the return and volume of swirl pot..then i would think the feed pump needs to flow the same or better than the 044....and you can not use just any pump as a feed for the 044....
As Adrain stated atmospheric pressure is 1 bar, so by definition fuel pressure is 1 bar, but when we are talking about pressurizing we are talking about putting an aditional positive pressure in relation to atmospheric pressure.
This is the starting point, if you fill a tank with 1ft deep of fuel and put a hose to the outlet pointing staright up, the fuel would rise 1ft up the tube, to pressurize the tank above atmospheric, this would push the fuel much higher up the tube...
Flow does not matter so much with a swirl pot because the fuel gets returned to the pot, and as pressure increases with boost and less fuel gets returned and more fuel gets burned, the lifter pump will need to keep up..... but basically nobody stays on full throttle all the time, so the lifter pump and volume on swirl pot and return from regulator means the swirl pot always stays in front.
So i have a low pressure lifter which flows 165 ltr/hr and a 044 which flows 260 ltr/hr...this is ok for a swirl pot due to the design and the way a car is driven.
But when two pumps are inline, one pump feeding another.. i assume they have to flow the same..but like Andy says when a pump does not need to create 4 bar pressure it will flow more....a stand alone 044 at 4 bar when you put your foot down only flows 180ltrs/hour, if you have high boost 1.5 bar then the flow drops even more and so on... so seen as though the most critical time is when you are on the power and the fact that the flow reduces with pressure...then the feed pump finds it easy to keep up...so although a m400 pump flows less at 3 bar it may flow more at 0.5 bar to what the 044 needs....
but as you can tell this is all guesstimates and talking theoretically...i think when linking the feed pump to the 044...the different fuel flows at different pressures need to be thought through.....to make sure the 044 is not going to be restricted by the feed pump..because if it is going to be restrictive then you are better running straight from the tank at atmospheric at least then you are sure of 200ltr/hr at 3 bar....
I am beginning to wonder if my 165ltr/hr lifter pump is enough...i would appreciate if somebody could follow me on this line of thought because it is not scientifical..this is all about working the flow in relation to fuel used this way i can work out the amount of fuel getting returned and add that to my lifter pump...
When i did some rough guesstimates it was based on the 044 flowing 200 ltr/hr...but i didnt take into account that by feeding the 044 at pressure its flow has just increased to 260 ltr/hr at 3 bar ....
... but at least at 4 bar when i have my foot down that flow will be reduced to 230 ltr/hr... and the lifter is 165 ltr/hr at 7psi, i assume it will flow a bit more at 5psi...plus the returned fuel from the 044 will be getting added to that flow.So with a swirl pot the critical part of this is return flow from the 044, I do not know the real maths so i have to just do some like for like comparisons...and first i think .."is there any way my car can use 260 ltr/hr?"... thats nearly 5 full tanks in 1 hour...i am thinking not....
So lets err on the safe side and say 6mpg going full whack around top gear track, thats 50 litres per 100km - 0.5 litre per km, thats 1.5 litre for every lap as the track is 3km long.
Lets err on the safe side even further and say 2 litre per lap, thats 1 min 20 per lap, so a full tank gets 30 laps...i think i am way safe on that..so a full tank lasts 40 minutes...thats 60 litres in 40 minutes...so lets say 90 ltr/hr fuel used.... so if the 044 is flowing 230 ltr/hr at 4 bar..then it would stand to reason that 140 ltr/hr gets returned??...
( on a side note.....With understanding the amount of fuel getting returned and constantly recirculated it is easy to understand why the fuel can get heated from underhood temps and local coolant pipes.... and I am better understanding why it had such an effect on performance when i reduced underhood temps and heat insulated the fuel return pipe, tank and the fuel lines.
When i say affect on performance... my power loss on scorching hot days used to be noticeable.. i used put it all down to air intake temps and IC...but soon discovered hot expanded fuel was playing just as big part in power loss)
I think i am well covered with the lifter and swirl pot system but we need Justin to come along and do the maths with having two pumps inline, as without the return and volume of swirl pot..then i would think the feed pump needs to flow the same or better than the 044....and you can not use just any pump as a feed for the 044....
Edited by R0162 on Friday 23 March 12:46
Chris, remembering at all times that I know nothing about this, my logic is as follows:
If an 044 can flow 260 litres per hour, that's 4.333 litres per minute. How long from a standstill does it take to get to VMAX? 30 seconds? That's the max you're ever likely to be on WOT so I'll assume for a moment that you're returning NOTHING to your swirl pot - you might use 2.167 litres if your injectors could flow that much (which I'll bet they couldn't even on 100% duty cycle), therefore emptying the swirl pot in just under 25 seconds. But you're topping it up constantly with another pump.
Also, the moment you lift off - even slightly you're no longer using all that fuel and it's returning to fill that void.
I know there's a whole heap of things I've not calculated but my point is you'll never use the amount of fuel you're thinking you will as you're returning it on every bend, every braking area and every gear change.
If an 044 can flow 260 litres per hour, that's 4.333 litres per minute. How long from a standstill does it take to get to VMAX? 30 seconds? That's the max you're ever likely to be on WOT so I'll assume for a moment that you're returning NOTHING to your swirl pot - you might use 2.167 litres if your injectors could flow that much (which I'll bet they couldn't even on 100% duty cycle), therefore emptying the swirl pot in just under 25 seconds. But you're topping it up constantly with another pump.
Also, the moment you lift off - even slightly you're no longer using all that fuel and it's returning to fill that void.
I know there's a whole heap of things I've not calculated but my point is you'll never use the amount of fuel you're thinking you will as you're returning it on every bend, every braking area and every gear change.
It's very difficult to spec fuel pump to a fixed likely HP as engine efficiency can vary dependent upon spec and set up, size of injectors, boost being ran. We have seen Warbro pumps running on 500BHP cars with parallel fed rails, and 044 equipped cars running over 600bhp.
Bosch do two 044 pumps there's a 4-6 pump and a 10 Bar pump. The 10Bar pumps are over double the price and are simply the best ones from the production batches of "normal" 044's.
Double 044's seems like massive overkill to me, adding weight complexity and huge amounts of heat into the fuel for no obvious gain.
It also has the potential for catastrophe if one pump either fails or loses efficiency. I've not heard of anyone feeding an 044 with an in-line pump before and if you're running a system which needs the extra flow then it may help in that scenario.
Those flow rates seem close on the 044 but are slightly off Chris.
My Bosch sourced figures for the 044 show:-
1Bar 258 Ltr/Hr (10.1 Amps)
2Bar 276 Ltr/Hr (10.8 Amps)
3Bar 264 Ltr/Hr (11.2 Amps)
4Bar 252 Ltr/Hr (11.5 Amps)
5Bar 225 Ltr/Hr (12.5 Amps)
The Amp draw on an 044 is pretty high and the major downside of that is heat generation (and additional Alternator load). There are pumps with very similar flow and much lower Amp draw rates available. The 044 is often seen as the "perfect" pump which I don't think it is for a variety of reasons.
Good fuel system Design and planning helps a lot, most noise from pumps is generated by cavitation, which can mostly be avoided by ensuring that feed to the pump is as big and 'flow friendly' as possible.
Mike.
Bosch do two 044 pumps there's a 4-6 pump and a 10 Bar pump. The 10Bar pumps are over double the price and are simply the best ones from the production batches of "normal" 044's.
Double 044's seems like massive overkill to me, adding weight complexity and huge amounts of heat into the fuel for no obvious gain.
It also has the potential for catastrophe if one pump either fails or loses efficiency. I've not heard of anyone feeding an 044 with an in-line pump before and if you're running a system which needs the extra flow then it may help in that scenario.
Those flow rates seem close on the 044 but are slightly off Chris.
My Bosch sourced figures for the 044 show:-
1Bar 258 Ltr/Hr (10.1 Amps)
2Bar 276 Ltr/Hr (10.8 Amps)
3Bar 264 Ltr/Hr (11.2 Amps)
4Bar 252 Ltr/Hr (11.5 Amps)
5Bar 225 Ltr/Hr (12.5 Amps)
The Amp draw on an 044 is pretty high and the major downside of that is heat generation (and additional Alternator load). There are pumps with very similar flow and much lower Amp draw rates available. The 044 is often seen as the "perfect" pump which I don't think it is for a variety of reasons.
Good fuel system Design and planning helps a lot, most noise from pumps is generated by cavitation, which can mostly be avoided by ensuring that feed to the pump is as big and 'flow friendly' as possible.
Mike.
Mike Tuckwood said:
Double 044's seems like massive overkill to me, adding weight complexity and huge amounts of heat into the fuel for no obvious gain.
I've not heard of anyone feeding an 044 with an in-line pump before
Those flow rates seem close on the 044 but are slightly off Chris.
My Bosch sourced figures for the 044 show:-
1Bar 258 Ltr/Hr (10.1 Amps)
2Bar 276 Ltr/Hr (10.8 Amps)
3Bar 264 Ltr/Hr (11.2 Amps)
4Bar 252 Ltr/Hr (11.5 Amps)
5Bar 225 Ltr/Hr (12.5 Amps)
Good fuel system Design and planning helps a lot, most noise from pumps is generated by cavitation, which can mostly be avoided by ensuring that feed to the pump is as big and 'flow friendly' as possible.
Mike.
I agree Mike....i dont think the 6mm hole in the filter helps matters with the feed being flow friendly..but surely offering a pressurized feed is better...I've not heard of anyone feeding an 044 with an in-line pump before
Those flow rates seem close on the 044 but are slightly off Chris.
My Bosch sourced figures for the 044 show:-
1Bar 258 Ltr/Hr (10.1 Amps)
2Bar 276 Ltr/Hr (10.8 Amps)
3Bar 264 Ltr/Hr (11.2 Amps)
4Bar 252 Ltr/Hr (11.5 Amps)
5Bar 225 Ltr/Hr (12.5 Amps)
Good fuel system Design and planning helps a lot, most noise from pumps is generated by cavitation, which can mostly be avoided by ensuring that feed to the pump is as big and 'flow friendly' as possible.
Mike.
Those figures i got were off a website...probably not accurate...are those figures you posted as a stand alone or fed by another pump?
Most websites say the same and recommend the 044 is fed by another pump..i assume this recommendation must come from Bosch?
I think the guys with double bosch 044 do it more as a safety measure...as opposed to overkill..i.e. if one pump goes the car can still run off the other one?
Few comments:
Careful confusing atmospheric pressure and absolute pressure, i'm not sure what the pumps are quoted at. hydraulic equipment is usually spec'd by gauge pressure (zero at local atmospheric pressure). so if a pump is rated at 10bar then that is 10bar gauge pressure (11bar absolute).
Pressure due to the 'head' of fuel in the tank is calculated using the equation: Pressure = desity x gravity x distance from fluid level. The so if the Noble fuel tank is full (lets say 0.5m from pump position to the level in the fuel tank):
Pressure = 720 kg/m^3 x 9.81m/s^2 x 0.5m = 3532 Pa (0.035bar!)
I always remember the pressure at 10m depth im water is about 1bar (increases by 1 bar for every 10m deeper you go).
the reason it is good practice to position fluid pumps with a positive head of fluid delivery (i.e. below the tank) is it helps the pumps prime.
as far as running pumps in parallel and series. My F3 car has 2 low pressure lifter pumps which feed the swirl pot which houses a Bosch pump similar to the 044. It can run with just 1 lifter pump, the second just offers some redundancy. something people might consider if running this kind of system.
I don't really have any experience of running 2 pumps in series without the second being fed by another reservoir/collector tank. Is this common? are we sure bosch don't mean this, as in my F3 car??
What Andy GTT is getting at is quite right with regard to pressure and flow of a pump. Don't forget the flow out of a pump will reduce as the heat increases, the viscosity of the fuel reduces and hence the leakage in the pump is higher.
Thinking out loud... consider what the pipes before the first pump, inbetween 2 series pumps and after the last pump are seeing:
before the first pump - next to no pressure and the highest flow
inbetween the 2 pumps - some pressure and some flow
after the second pump - some pressure and some flow (more flow/pressure if the pump is a higher spec of course)
now if the second pump is pushing a higher flow and higher pressure then the pressure in the pipe between the 2 pumps will drop and hence the first pump will have an easier job pushing fluid and will speed up. so will the 2 pumps not find a flow balance? the only benefit of having 2 being the second pump has an easier time in life!
some commercial equipment (diggers etc) can have a pressurised tank in hydraulics. maybe a 3bar pressurised tank. this just reduced the risk of cavitation in whatever pump is being fed. Another pump feeding the 044 is doing sort of the same thing i think but of course no risk of not supplying enough flow. A pressurised tank is not necessary if the position of the pump is well thought out and the pipes feeding the pump are large enough to avoid cavitation.
anyway, some food for thought. can you tell i'm bed bound ill haha
cheers
James
Careful confusing atmospheric pressure and absolute pressure, i'm not sure what the pumps are quoted at. hydraulic equipment is usually spec'd by gauge pressure (zero at local atmospheric pressure). so if a pump is rated at 10bar then that is 10bar gauge pressure (11bar absolute).
Pressure due to the 'head' of fuel in the tank is calculated using the equation: Pressure = desity x gravity x distance from fluid level. The so if the Noble fuel tank is full (lets say 0.5m from pump position to the level in the fuel tank):
Pressure = 720 kg/m^3 x 9.81m/s^2 x 0.5m = 3532 Pa (0.035bar!)
I always remember the pressure at 10m depth im water is about 1bar (increases by 1 bar for every 10m deeper you go).
the reason it is good practice to position fluid pumps with a positive head of fluid delivery (i.e. below the tank) is it helps the pumps prime.
as far as running pumps in parallel and series. My F3 car has 2 low pressure lifter pumps which feed the swirl pot which houses a Bosch pump similar to the 044. It can run with just 1 lifter pump, the second just offers some redundancy. something people might consider if running this kind of system.
I don't really have any experience of running 2 pumps in series without the second being fed by another reservoir/collector tank. Is this common? are we sure bosch don't mean this, as in my F3 car??
What Andy GTT is getting at is quite right with regard to pressure and flow of a pump. Don't forget the flow out of a pump will reduce as the heat increases, the viscosity of the fuel reduces and hence the leakage in the pump is higher.
Thinking out loud... consider what the pipes before the first pump, inbetween 2 series pumps and after the last pump are seeing:
before the first pump - next to no pressure and the highest flow
inbetween the 2 pumps - some pressure and some flow
after the second pump - some pressure and some flow (more flow/pressure if the pump is a higher spec of course)
now if the second pump is pushing a higher flow and higher pressure then the pressure in the pipe between the 2 pumps will drop and hence the first pump will have an easier job pushing fluid and will speed up. so will the 2 pumps not find a flow balance? the only benefit of having 2 being the second pump has an easier time in life!
some commercial equipment (diggers etc) can have a pressurised tank in hydraulics. maybe a 3bar pressurised tank. this just reduced the risk of cavitation in whatever pump is being fed. Another pump feeding the 044 is doing sort of the same thing i think but of course no risk of not supplying enough flow. A pressurised tank is not necessary if the position of the pump is well thought out and the pipes feeding the pump are large enough to avoid cavitation.
anyway, some food for thought. can you tell i'm bed bound ill haha
cheers
James
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