[supra2800turbo]

Hello,

I was wondering ... what if the wires that goes to the fuel pump are too thin at theres a loss of voltage in it, so that the fuel pump is running like 1 voltage lower than what it should? or something...

Will I get anything out of it if I install thicker wires with less loss in ?

I need to use my fuel pump 100% ...

 

[Hosam]

The thickness of the wiring mainly affects the amount of current flowing through the wiring. The voltage essentially remains constant.

 

[supra2800turbo]

So what you're saying is, the thicker the wire the less voltage loss there will be - and more fuel will flow?

 

[Dave A.]

The longer the length of wire of a given wire size (AWG) the more resistance that you add to the circuit. A lot depends on the amount of current that's needed for the fuel pump to run at it's max. efficiency. Chances are that the fuel pump motor draws a fair amount of current when under load, but probably not more than about 5 amps, if that. Try measuring the DC voltage across the two terminals of the fuel pump with the engine running at fast idle and see if the reading is lower than the normal 13-14.5 volts and see if the fuel pump wiring gets warm to the touch. I'm guessing that you won't see any problems, but at any rate, increasing the wire size in the fuel pump circuit won't hurt a thing. The question is, is this really necessary and to your advantage?

 

[supra2800turbo]

Dave, do you have any ideas of how long the wires (voltages) are that goes to the fuel pump from a power source? I have a formula to calculate the power loss etc.

Well - its just that if I was gonna install a walbro some day anyway, then it might as well get enough power available

 

[Dave A.]

No, I have no clue as to the length of wiring in the fuel pump circuit. Check the specs. on the Walbro pump. If the new pump draws more current than the stock pump, then increasing the wire size could prove beneficial. If the new pump draws the same or less amount of current than the stock pump, then the factory wiring should be sufficient.

 

[supra2800turbo]

Hmm ... yes ... you're right Dave... again :wink:

 

[MKIIBeater]

I think regardless of the pump that rewiring with at leist 12 gauge wire directly from the batter (with a relay of course) will better the flow when under "high" load. When your at high RPM, especially when sustained, the pump has to take a loss in voltage. Even if the pump will come close to operating at its normal rate, wouldn't rewiring it with heavier gauge wire give it more voltage at that specified rpm where it drops off and maybe even stop/lessen the drop causing better flow regardless? I just realized how long that sentence was :shock: , anyway I think its a good idea no matter what, especially if youll be going walbro soon.