how do i rewire my walbro fuel pump
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From: Seattle / Kalifornia
Originally Posted by bluemetals2k' timestamp='1289069542' post='19775752
Mod you better just close this one 
This site welcomes alternative opinions and reasoned thought. What it doesn't tolerate is personal abuse.
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From: Sydney
Including me. I'm standing on the shoulders of geniuses and I'm wearing cleats!
Seriously, has anyone tested the temperature of the power wire under FI load? It may not have burnt out but it may be getting warmer and increasing it's resistance.
Seriously, has anyone tested the temperature of the power wire under FI load? It may not have burnt out but it may be getting warmer and increasing it's resistance.
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From: Long Beach, CA
Originally Posted by averageJoe,Nov 4 2010, 08:16 PM
why do you want to do this anyways?
just stop what you are about to do before you ruin your pump or short out something and cause a fire.
Yes, you are wasting your time and gain no benefit by running a ridiculously large gauge wire for something (fuel pump) that doesn't draw that much current.
Even if it did 'need' a 10gauge wire, you would surely melt the small wire and have issue, but you do NOT need 10g for the pump.
if you want more fuel, (for whatever reason that you did NOT include in your post), get a higher flowing pump than you currently have without hacking up your wiring.
Get a higher flowing pump, then measure the current draw to determine if you need a thicker gauge wire.
What your asking to do is over-volt the pump by running off the battery, which is being charged by the very noisy (electronically) alternator, which, in turn is not good if you want constant power to your precious fuel pump.
just stop what you are about to do before you ruin your pump or short out something and cause a fire.
Yes, you are wasting your time and gain no benefit by running a ridiculously large gauge wire for something (fuel pump) that doesn't draw that much current.
Even if it did 'need' a 10gauge wire, you would surely melt the small wire and have issue, but you do NOT need 10g for the pump.
if you want more fuel, (for whatever reason that you did NOT include in your post), get a higher flowing pump than you currently have without hacking up your wiring.
Get a higher flowing pump, then measure the current draw to determine if you need a thicker gauge wire.
What your asking to do is over-volt the pump by running off the battery, which is being charged by the very noisy (electronically) alternator, which, in turn is not good if you want constant power to your precious fuel pump.
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From: Long Beach, CA
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Does anyone know how big of a difference it makes having the wiring like described in this thread VS having a 10ga from a relay wired DIRECTLY to the walbro. By that I mean taking the hanger out, and running the power/ground from the points of contact on the walbro out the hanger, to the relay.
I ask this because I've been running this cheater mod for months now without issue, but I have to drop in a new hanger soon (already have it), and figured I might as well give it some BEEFY wiring without going through a SMALL gauge wire first.
I realize its more difficult and time consuming, but i feel its the right way to go if you already have the hanger out.
Thoughts? Serious responses only please. Thanks
I ask this because I've been running this cheater mod for months now without issue, but I have to drop in a new hanger soon (already have it), and figured I might as well give it some BEEFY wiring without going through a SMALL gauge wire first.
I realize its more difficult and time consuming, but i feel its the right way to go if you already have the hanger out.
Thoughts? Serious responses only please. Thanks
Joined: May 2006
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From: Dodging bullets in L.A. Calif
This wire capacity graphic was not meant for automotive applications, but it'll give you an idea.
the ~18 gauge OEM wire should handle about 10 - 12 amps
Walbro pumps draw about 10A @ 70 psi or ~26psi boost (static fuel pressure of 43.5psi + 26psi boost, more than what most people run)
So the OEM wire should be good enough to run a single Walbro pump
But if you ever think of going to a more current demanding pump, like a Bosch 044.... why not use heavier gauge wire if you're not weary about doing the mod!
the ~18 gauge OEM wire should handle about 10 - 12 amps
Walbro pumps draw about 10A @ 70 psi or ~26psi boost (static fuel pressure of 43.5psi + 26psi boost, more than what most people run)
So the OEM wire should be good enough to run a single Walbro pump
But if you ever think of going to a more current demanding pump, like a Bosch 044.... why not use heavier gauge wire if you're not weary about doing the mod!
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i feel this mod is 100% needed on any FI s2000, summit racing sells a generic fuel pump rewire kit that works great and includes all wiring and a circuit breaker to eliminate all hassles. price is around 30$. While your working on the pump you might as well depress the bypass valve so higher fuel pressures can be run and be sure to wire it all the way down to the pump itself with the larger wiring, your totally defeating the purpose if any stock wiring is left.
Joined: Apr 2008
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From: Burbs of Philly, PA
i feel this mod is 100% needed on any FI s2000, summit racing sells a generic fuel pump rewire kit that works great and includes all wiring and a circuit breaker to eliminate all hassles. price is around 30$. While your working on the pump you might as well depress the bypass valve so higher fuel pressures can be run and be sure to wire it all the way down to the pump itself with the larger wiring, your totally defeating the purpose if any stock wiring is left.
Has anyone rewired the walbro (or any pump) all the way down to the pump itself? If so is there a DIY out there?
Would this mod also benefit the new Full blown 340 lph fuel pump too?
Thanks
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From: South Florida
Anyone thinking of doing this just do it. First off if ur running a single pump and making 550 or less it's super simple to do.
Buy a relay at pepboys, but some wire and a fuse. U can splice into the stock wiring for the pump. Remember this mod is not because the stock wiring is bad, it's because the stock wiring doesn't allow 14 volts to the pump. Once u rewire it the pump will get way louder and sound healthy.
Stock I think it only sees like 12 or 11 Volts. Something pathetic. Now if ur gonna rewire all the way to the pump then might as well throw in a 340 at the same time
Buy a relay at pepboys, but some wire and a fuse. U can splice into the stock wiring for the pump. Remember this mod is not because the stock wiring is bad, it's because the stock wiring doesn't allow 14 volts to the pump. Once u rewire it the pump will get way louder and sound healthy.
Stock I think it only sees like 12 or 11 Volts. Something pathetic. Now if ur gonna rewire all the way to the pump then might as well throw in a 340 at the same time