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whitestang04GT
04-04-2005, 11:21 PM
Can anyone give me a link or tech article on rewiring the stock fuel pump with a larger gauge wire to help minimize the voltage drop on the stock pumps..... Thanks in advance......

Davesnake
04-04-2005, 11:57 PM
Here you go

http://www.modularfords.com/forums/showthread.php?t=23568

Dave

whitestang04GT
04-05-2005, 09:06 AM
Here you go

http://www.modularfords.com/forums/showthread.php?t=23568

DaveAwesome - Thanks :bounce:

Dave B.
04-05-2005, 09:50 PM
I find this idea to be a very interesting concept,
can you tell us more?
such as what is the actual proven gains?

are you saying we could get more RPM on the PUMP MOTOR it self by doing this?

I ask this because I would be very surprised to find out Ford used smaller gauge wire than would be requiared, in fact,

Being a former commuter Airline pilot, we were always told the FAA requiared six (6) gauges larger wire than any particular peice of equipment needed, and that automotive requiared four (4) sizes larger,

So under those guide lines, the pump should already have bigger than nessasary wiring. Please tell us more about this, thanks Dave B.

whitestang04GT
04-05-2005, 10:58 PM
I find this idea to be a very interesting concept,
can you tell us more?
such as what is the actual proven gains?

are you saying we could get more RPM on the PUMP MOTOR it self by doing this?

I ask this because I would be very surprised to find out Ford used smaller gauge wire than would be requiared, in fact,

Being a former commuter Airline pilot, we were always told the FAA requiared six (6) gauges larger wire than any particular peice of equipment needed, and that automotive requiared four (4) sizes larger,

So under those guide lines, the pump should already have bigger than nessasary wiring. Please tell us more about this, thanks Dave B.
It looses amperage when you have heavily modified the motor under heavy acceleration......many variables......Its a good mod if you are pushing more than 500rwhp IMO......

Dave B.
04-05-2005, 11:04 PM
who brought forth this concept? do you know?
I should be pushing 550 HP at the crank and I have a fuel pressuer gauge, I have spent a lot of time watching it under all kinds of condition and I can tell you that under hard acceleration the pressure builds, to a point then stays at a peak, I guess I need next time I hit it hard to see what it builds up to, but at no time does it start to drop, I have 18,000+ miles on the car, and have added a lot of fuel with the predator, but the pressure goes up during acceleration, not down,

whitestang04GT
04-05-2005, 11:10 PM
who brought forth this concept? do you know?Don't know directly......I was told it had been dyno proven....But hasn't everthing........???Got me??....I saw somewhere another docment talking about someone actually measuring the voltage drop.....???.....But it does make sense to me...Like an extentsion cord, you increase the load at the other end, even heat alone, you create more amperage drop......Common physics......

Dave B.
04-05-2005, 11:16 PM
Yes I do agree that it sounds right, well I cannot tell you for sure, but if the voltage is dropping, it may be from the altenator being disconected from the system do to it reaching a high RPM, sort of how the A/C compressor does,

If the altenator were to cut out of the charging system at the moment of hard accell, yes it would look like a voltage drop as only the battery would be powering the pump, but I cannot say for sure the altemator cuts out, but I find that easier to believe than the wire being to small. Know what I mean?

whitestang04GT
04-05-2005, 11:40 PM
Yes I do agree that it sounds right, well I cannot tell you for sure, but if the voltage is dropping, it may be from the altenator being disconected from the system do to it reaching a high RPM, sort of how the A/C compressor does,

If the altenator were to cut out of the charging system at the moment of hard accell, yes it would look like a voltage drop as only the battery would be powering the pump, but I cannot say for sure the altemator cuts out, but I find that easier to believe than the wire being to small. Know what I mean?True....Great point......More food for thought.......But wouldn't the battery make up for what the alternator doesn't??

Dave B.
04-06-2005, 12:13 AM
no, the battery would not put out the voltage an alternator at high RPM would, if you get a voltage tester, hold it on your battery terminals with the engine off, you should have about 12.3 volts give or take,

but then start your car and do it and the altenator will bring it up to about 13.8 to 14.5 or more, and voltage is hands down, the item electric motors need to spin, not so much as amps, but voltage is the main driving factor for eletric motors, yes amps sre important, the battery has plenty of amps by its self, but I just think this idea is one of those folk tales you know?

Dave B.
04-06-2005, 01:04 AM
AND ANOTHER THING,
does anyone that has done or doing this have a fuel pressure gauge?

I bet not, if they have a fuel pressure gauge, like I do, they would see that the fuel pressure, on the 2003's anyway, continualy goes up to its max and stays there, I would bet to say the guys doing this mod, are acting without having a way to see what the fuel press is actualy doing, thus assuming somethings going wrong, get the gauge first and you will all see what I mean,

Now if its an older car,,,,,,,,,,that may indeed be a differant story all together

bassin247
04-06-2005, 02:25 PM
This mod does work. My background is in mechanical engineering but I did minor in Electrical.

The wire gauge is small. I think it's 16 gauge. With the wire size so small and the current approaching 20 amps the wire itself acts as a resistor. Voltage drops over 1.5 volts have been measured. Increasing the wire size reduces the voltage drop. If you decrease the voltage drop from 1.5 volts to .5volts you gain 1/12 or 8.3% fuel flow.

This has been tested and proven. Jon Lund or Dustoff on ModularFords has fuel pump duty cycle datalogs before and after the upgrade. With the same mods, it has show the upgrade results in the same fuel pressure at the same rpm with less fuel pump duty cycle.

Davesnake
04-06-2005, 07:02 PM
This mod does work. My background is in mechanical engineering but I did minor in Electrical.

The wire gauge is small. I think it's 16 gauge. With the wire size so small and the current approaching 20 amps the wire itself acts as a resistor. Voltage drops over 1.5 volts have been measured. Increasing the wire size reduces the voltage drop. If you decrease the voltage drop from 1.5 volts to .5volts you gain 1/12 or 8.3% fuel flow.

This has been tested and proven. Jon Lund or Dustoff on ModularFords has fuel pump duty cycle datalogs before and after the upgrade. With the same mods, it has show the upgrade results in the same fuel pressure at the same rpm with less fuel pump duty cycle.



Thanks for clearing that up bassin.....guess who's house I'm going over when I do this mod....hint,hint..... ;)


Dave <------ hates wiring

Dave B.
04-06-2005, 09:38 PM
No kidding, I wounder if that smaller wire will be enlarged for the 05?

bassin247
04-08-2005, 03:12 AM
No kidding, I wounder if that smaller wire will be enlarged for the 05?
Probably not. They sized the wire/pumps for the HP the car was intended to make from the factory + a little overhead. My stock pumps supported 550rwhp before they maxed out.