High power fuel system specing
Discussion
Im planing to upgrade my fuel system as im sort of on the limit of a standard high power setup hence I want to open up a bit of margin rather than run on the limit.
Currently I have a bosch 044, this can flow up to around 50-600bhp assuming everything is perfect... now I could run a 2nd pump and I have a few to choose from in the garage including a brand new cossie pump capable of 350bhp.
The issue I have with this setup is that if something fails I will have a setup that runs the car with no issues at all until I nail it were it will lean out and destroy the engine.
Next option is to go to a Aeromotove A1000 but I will need a controler etc and this will be around £800 for a fully sorted setup wereas teh dual system will cost me very little as I already have the pumps.
Is there a middle ground, maybe something that can monitor the pressure from each of my bosch pumps and flag when there is an issue etc?
I want to avoid spending silly money unless I have to
Cheers
Currently I have a bosch 044, this can flow up to around 50-600bhp assuming everything is perfect... now I could run a 2nd pump and I have a few to choose from in the garage including a brand new cossie pump capable of 350bhp.
The issue I have with this setup is that if something fails I will have a setup that runs the car with no issues at all until I nail it were it will lean out and destroy the engine.
Next option is to go to a Aeromotove A1000 but I will need a controler etc and this will be around £800 for a fully sorted setup wereas teh dual system will cost me very little as I already have the pumps.
Is there a middle ground, maybe something that can monitor the pressure from each of my bosch pumps and flag when there is an issue etc?
I want to avoid spending silly money unless I have to
Cheers
Steve_D said:
Use an in tank pump to feed a swirl pot.
Use the spare pump as a pre-pump for the 044.
Fit a pressure switch to tell you when pressure drops below a limit or a pressure sensor connected to a digital dash (Stack etc) with a preset warning for low pressure.
Steve
Wiring pumps directly in series is almost pointless. And with a swirl pot, you effectively do run pumps in series anyway.Use the spare pump as a pre-pump for the 044.
Fit a pressure switch to tell you when pressure drops below a limit or a pressure sensor connected to a digital dash (Stack etc) with a preset warning for low pressure.
Steve
You don't say what EMS your car runs with, Assuming you really need high power, then a programmable aftermarket (MoTeC, Pectel etc etc) EMS would be worth it's weight in BHP, and with that flexibility, just sensor the fuel pressure, correct the fuelling for minor fluctuations, and then set a zero trim at lower pressures to just turn off the engine if pressure drops below some critical level.
I run with double 044 pumps but in series, and i have a custom SMPS that supplies up to 20v to the pumps in transient conditions to delivery an increased fuel mass at up to 12bar (gauge) rail pressure, also i have a custom returnless fuel system that does fuel pressure control (allows me to cal fuel pressure vs load, so i run high pressure at high load, and a more normal 5bar at idle to maximise IJPW at light loads) (pumps in series "share" the total fuel pressure across them (assuming they are the same type of pump) and hence can deliver an increased fuel mass at high pressures (to decide between parrallel and series, you need to characterise your pump vs battery voltage and pressure head, then decide which way to plumb up)
I run with double 044 pumps but in series, and i have a custom SMPS that supplies up to 20v to the pumps in transient conditions to delivery an increased fuel mass at up to 12bar (gauge) rail pressure, also i have a custom returnless fuel system that does fuel pressure control (allows me to cal fuel pressure vs load, so i run high pressure at high load, and a more normal 5bar at idle to maximise IJPW at light loads) (pumps in series "share" the total fuel pressure across them (assuming they are the same type of pump) and hence can deliver an increased fuel mass at high pressures (to decide between parrallel and series, you need to characterise your pump vs battery voltage and pressure head, then decide which way to plumb up)
stevieturbo said:
.....Wiring pumps directly in series is almost pointless.......
Many places I have been online recommend fitting an 044 after another pump stating that it increases fuel flow. One of these sites being Camskill http://www.camskill.co.uk/products.php?plid=m10b95...My reason for my original post was that HP fuel pumps don't like to suck so an in-tank pump overcomes this problem.
The pump supplying a swirl pot is unlikely to assist an HP pump as there will be very little pressure since the return line to the tank goes from the swirl pot. My recommendation here was 3 pumps, one in tank supplying the swirl, then 2 in line with the first increasing the output of the second.
Andy does not say how much power he is looking for but knowing his projects I suspect he my only need a little more than the rated output of a single 044.
Steve
The benefit to flow of pumps in series is minimal. They may be able to provide a higher pressure easier....but considering the 044 is pretty stable to around 7-8bar anyway...that does mean using them in series is pretty pointless.
If they are in parallel, you WILL have double the flow available. It's as simple as that really.
But the OP doesnt give enough details to spec a system
If its just a fairly simple 600bhp, then even a couple of Walbros would be more than adequate ( plumbed correctly in parallel of course ) and cost less than £200.
If they are in parallel, you WILL have double the flow available. It's as simple as that really.
But the OP doesnt give enough details to spec a system
If its just a fairly simple 600bhp, then even a couple of Walbros would be more than adequate ( plumbed correctly in parallel of course ) and cost less than £200.
Steve_D said:
Many places I have been online recommend fitting an 044 after another pump stating that it increases fuel flow. One of these sites being Camskill http://www.camskill.co.uk/products.php?plid=m10b95...
And regardless of what any site says. In series, the two pumps will NEVER be able to flow any more than the highest ability of any single pump in that system.So of P1 flows 250lph at 0psi and P2 200lph at 60psi. The entire system can never flow more than 250lph, as P1 is the restriction
If you use the same two 200lph @ 60psi pumps in parallel. They will flow 400lph.
So unless you have a need for crazy pressures beyond what a normal 044 can supply, its pointless. And if you need those pressures, you've designed the fuel system wrong.
And whilst voltage boosters may be popular in the US, I wouldnt even consider one unless it was a last resort. I'd rather just build the fuel system correctly in the first place.
Its not for my project so its not the 900bhp Im planning with that 
.... this is for my Noble, currently it runs a single 044 but this is only technically capable of flowing enough fuel and is way to marginal for me... its a turbocharged V6 running a std MBE.
I have been told that running the pumps in sequence can increase the capacity of the 044 as the first pump doesnt see any pressure at all due to the next pump and the final pump doesnt need to suck and already has pressure going into it.... I really want the end result to be capable of flowing a comfortable 700bhp and the more the better.
Needs to hold 4bar with 6bar under boost.
I plan a swirl pot in the long run but its not a requirement right now, just want the correct volume of fueling
.... this is for my Noble, currently it runs a single 044 but this is only technically capable of flowing enough fuel and is way to marginal for me... its a turbocharged V6 running a std MBE.I have been told that running the pumps in sequence can increase the capacity of the 044 as the first pump doesnt see any pressure at all due to the next pump and the final pump doesnt need to suck and already has pressure going into it.... I really want the end result to be capable of flowing a comfortable 700bhp and the more the better.
Needs to hold 4bar with 6bar under boost.
I plan a swirl pot in the long run but its not a requirement right now, just want the correct volume of fueling
andygtt said:
Its not for my project so its not the 900bhp Im planning with that .... this is for my Noble, currently it runs a single 044 but this is only technically capable of flowing enough fuel and is way to marginal for me... its a turbocharged V6 running a std MBE.
I have been told that running the pumps in sequence can increase the capacity of the 044 as the first pump doesnt see any pressure at all due to the next pump and the final pump doesnt need to suck and already has pressure going into it.... I really want the end result to be capable of flowing a comfortable 700bhp and the more the better.
Needs to hold 4bar with 6bar under boost.
I plan a swirl pot in the long run but its not a requirement right now, just want the correct volume of fueling
See post above re-series pumps..... this is for my Noble, currently it runs a single 044 but this is only technically capable of flowing enough fuel and is way to marginal for me... its a turbocharged V6 running a std MBE.I have been told that running the pumps in sequence can increase the capacity of the 044 as the first pump doesnt see any pressure at all due to the next pump and the final pump doesnt need to suck and already has pressure going into it.... I really want the end result to be capable of flowing a comfortable 700bhp and the more the better.
Needs to hold 4bar with 6bar under boost.
I plan a swirl pot in the long run but its not a requirement right now, just want the correct volume of fueling
If you are external pumps, then even a pair of 909's would be more than adequate ( cheaper alternative to an 044 )
Or a pair of inline external Walbros would do.
Obviously both of the above plumbed in parallel. Although as the pressure isnt going crazy, you could add almost any decent efi pump in parallel with your 044 to boost performance.
I assume the existng setup doesnt have an in-tank pump of any kind ?
If you wanted a swirl tank setup. Cheapest would be use any efi pump to supply the swirl tank ( or a high volume low pressure pump ). Then a pair of 909's or Walbros feeding the engine from the tank. This would supply more than enough fuel for your needs
If using multiple pumps, there probably isnt much need for the expense of 044's for a very safe 700bhp.
is there an easy way to wire up some sort of warning light for each fuel pump if one failes? my large concern is that if one fails the other will run engine absoluetlly fine until i really nail it then bang!
other option is a full dual system of cutting the fuel rail and having a pump run each bank... one goes down i will notice and it wont go bang.
other option is a full dual system of cutting the fuel rail and having a pump run each bank... one goes down i will notice and it wont go bang.
stevieturbo said:
And if you need those pressures, you've designed the fuel system wrong.
really? you must pop over to those stupid WRC and F1 boys and let em know that, that crazy lot run 16bar and 50 to 80bar respectively............(ah, good old Pistonheads, where sweeping statements rule
)The ONLY way to determine if you need twin pumps in series or parallel is to characterise a single pumps flows vs pressure vs voltage actually in the fuel system in question (i.e. same pipe length, regulator(s), wiring size and length etc) What you find is that the pump will have a fairly linear flow rate drop vs pressure head intially, then as (principally due to magnetic saturation), that drop becomes a knee point, and a very rapid flow rate drop occurs to a stalled pump at some critical head value.
Once you know this characteristic, then you can plot the two operating points to determine which will provide the most flow (and give the longest pump life & least current draw).
(series point is the flow of a single pump at HALF the total operating pressure, parallel point is 2 x the flow at the total operating pressure, and depending upon lots of factors like wiring resistance and pump heating / I2R losses etc, one will be bigger than the other)
Voltage control (and overboost) on a fuel pump is actually a very good idea. When you consider the length of time that you need the maximum fuel flow for(esp in a road car), carrying around multiple pumps and things, and pumping gallons of fuel around the system, just to return it to the tank is a bit non-optimum. Going to a voltage controlled single pump overboosted returnless fuel system saved 3.8kg on my car. (and allowed much better transient control of AFR due to being able to run smaller flow rate injectors, and find a 8bhp increase in peak power due to running a shorter total injector pulse time allowing a better injection angle)
Anyway, thats a bit outside the scope of the original question, but my advice stands, i.e., before just changing stuff, measure what you have and it's charactastics, and use that information to decide what to change
I somehow doubt he is building either an F1 or WRC car, and I also doubt a WRC car uses those sorts of pressures.
At least I have certainly never seen any WRC cars with fuel systems like that, and there are plenty of them rallying here in Ireland.
No idea about F1 though, but that is a different kettle of fish entirely.
The voltage boosters can be effective, and your logic makes sense about their use.
I'd still rather build a simple fuel system that always flows enough whether it be at 11 volts, or 14 volts. Any normal range the car will see during usage.
At least I have certainly never seen any WRC cars with fuel systems like that, and there are plenty of them rallying here in Ireland.
No idea about F1 though, but that is a different kettle of fish entirely.
The voltage boosters can be effective, and your logic makes sense about their use.
I'd still rather build a simple fuel system that always flows enough whether it be at 11 volts, or 14 volts. Any normal range the car will see during usage.
Subaru WRC fuel pump system, two 044's in parallel:
http://mez.co.uk/graphics/liftpump1.jpg
And the 044 that's in my Dakar was straight out of a WRC car also (they replaced both after each event). Genuine 044's can be had of ebay for £90-100 - hardly expensive compared to the billet yank stuff.
http://mez.co.uk/graphics/liftpump1.jpg
And the 044 that's in my Dakar was straight out of a WRC car also (they replaced both after each event). Genuine 044's can be had of ebay for £90-100 - hardly expensive compared to the billet yank stuff.
eliot said:
And the 044 that's in my Dakar was straight out of a WRC car also (they replaced both after each event). Genuine 044's can be had of ebay for £90-100 - hardly expensive compared to the billet yank stuff.
Go careful buying Bosch pumps from eBay....they arent always genuine, but far eastern copies! One way of telling is if they have a non return valve on the output side. £90-100 is a little cheap, unless they have old ones in stock as Bosch have just put their prices up quite significantly!JontyR said:
eliot said:
And the 044 that's in my Dakar was straight out of a WRC car also (they replaced both after each event). Genuine 044's can be had of ebay for £90-100 - hardly expensive compared to the billet yank stuff.
Go careful buying Bosch pumps from eBay....they arent always genuine, but far eastern copies! One way of telling is if they have a non return valve on the output side. £90-100 is a little cheap, unless they have old ones in stock as Bosch have just put their prices up quite significantly!eliot said:
Subaru WRC fuel pump system, two 044's in parallel:
http://mez.co.uk/graphics/liftpump1.jpg
Thats an old S5 setup, very different fuel system from S7 onwards!!http://mez.co.uk/graphics/liftpump1.jpg
Max_Torque said:
eliot said:
Subaru WRC fuel pump system, two 044's in parallel:
http://mez.co.uk/graphics/liftpump1.jpg
Thats an old S5 setup, very different fuel system from S7 onwards!!http://mez.co.uk/graphics/liftpump1.jpg
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