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  1. #1
    Ultimo Miembro Fantástico Gigantesco ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD's Avatar
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    Default Why the Walbro pump gets a bad rep.

    Many people complain that their Walbro 255lph pump is "too loud", or "annoying". Some go so far as to switch it out in favour of the more expensive Supra TT fuel pump.

    However, some people don't have this problem. Some people can't even hear the Walbro fuel pump running, and question up and down WTF those "complainers" were talking about.

    Are there some "special" Walbro pumps out there? Is this a manufacturing defect, that some luck out and get 'quiet' versions? NO and NO.

    There's no magic going on here. The answer is quite simple actually.

    Some facts. The standard 3S-GTE is equipped with a fuel pump resistor. This resistor is bypassed via the fuel pump relay when the ECU tells it to under conditions of high load. This resistor limits the amount of voltage supplied to the fuel pump.

    A common modification and/or shortcut for 3sgte owners and swappers is to jump power directly to the fuel pump. There are a variety of ways to do this. You can install a jumper wire between two of the terminals of the fuel pump relay. Swappers often install a jumper wire between the B+ and the FP pins in the diagnostics box in order to get their car to run.

    What is the effect of this modification? The fuel pump resistor, is bypassed all the time, and full voltage is supplied to the fuel pump all the time. Some people claim horsepower gains from this mod, which is a complete load of poo. Remember, your Air/Fuel ratio is your Air/Fuel ratio. The stock ECU runs the engine excessively rich. Is adding a little more power to the fuel pump, thus overpowering the FPR slightly going to give you more power, when you are already running ungodly rich? NO!

    So there is NO reason to do this mod to a standard car. For swappers, it is often a short cut since people are often too lazy to wire in the 3rd ECU plug. Guess what? The 3rd ECU plug contains the wire that operates the fuel pump relay! gasp. It is conveniently labelled "FPR" in case you were wondering.

    Okay, you now know what everything does and why people do it. How do you wire in the fuel pump relay and resistor properly? It is quite simple. Here is the wiring schematic for the FPR system from the ECU. Connect a few wires and toss them in your wiring harness when you are doing the swap.



    So I've been rambling a while. What does any of this BS have to do with the subject line? Glad you asked.

    When the Walbro fuel pump is given full power, it is indeed quite loud. The other day I was playing with my car and gave the fuel pump direct battery voltage. I was astonished that I could hear my fuel pump working! I had never been able to hear it before.

    This is where the problem comes in. People bypass the fuel pump relay and resistor, thus giving the fuel pump full power! So yes, of course it is going to be loud! However, if you wire the FPR system in properly, you will enjoy a quiet, unnoticeable fuel pump. You won't even hear it at idle, much less when you are actually driving.

    So if you are complaining about the noise of the walbro pump, I suggest you reevaluate how you have gone about altering the systems in your 3S-GTE. Don't bypass the fuel pump resistor, and wire in your 3rd ECU plug!!

    Thats all.

    C.N.:
    -fuel pump resistor limits voltage supply to fuel pump
    -bypassing this resistor supplies full voltage to fuel pump
    -wiring the 3rd ecu plug, specifically the FPR pin, is easy
    -the walbro pump is loud when given full voltage
    -dont bitch at me that your walbro pump is loud when you have bypassed the FP resistor
    Last edited by ChrisD; 07-01-2012 at 06:45 AM.
    1988 ST165 2.2L @ 370awhp
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  2. #2
    Senior Member RickyNo will become famous soon enough

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    Good writing.
    I tend to say that if you do something, do it right or just don't.
    You morons have vacancy signs on your asses and my foot's looking for a room!

  3. #3

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    Supposedly the point of bypassing the relay was you get a [slight, like .1 seconds or whatever] jump on full pressure when you hit the throttle.
    Dunno how much it matters.

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  4. #4

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    chris, i have another theory why the pump is louder for some people then for others.

    1st of all, lets not kid anyone. even the people at walbro admited their pumps are much much louder oem pumps, when i called them. they also got the nickname Whinebro from many owners.

    when i first did my swap, i noticed the pump was louder then a stock one, but nothing annoying. then after a few months it started getting louder and louder. it got so bad, that you could hear nothing but the pump when standing 20feet away from the car. i wish i had a video of it, because you guys would be amazed at how loud it was.

    to walbros credit, it never failed, but since the noise got so loud i decided to swap it out for a supra oem pump. this is when i think i figured out why my pump was so loud. during installation, i crimped the electrical connectors that come with the install kit, and used electrical tape around them so that everything would be nice and secure. over 6 months, the tape started melting, and cloged the little filer on the pump, making it work harder then it has to, to suck fuel in. the filter was crazy black compare to my oem filter that was there for years.
    im willing to bet that most of the people that report this problem didnt know that you cant use electrical tape in the tank, and that is why they report the problem.

    i now have an oem supra pump and it runs quiet as a stock pump, even without the fuel pump resistor.
    Boosted. Tuned. Ready.

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  5. #5

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    here is a pic of the 2 filters. the one on the left is the wabro filter after 6 months of use. notice all the black stuff from the tape. the one on the right is my oem filter after years of use with the 5sfe. notice how clean it is after all those years of use.

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  6. #6
    Ultimo Miembro Fantástico Gigantesco ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD's Avatar
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    Lagos,

    That could be a problem as well. Clogging up your fuel filter is never a good idea.

    Now, how is your pump wired? Have you bypassed the fuel pump resistor?

    I have tested this. With the pump receiving battery power, it is VERY loud! When power is sent through the resistor first, you can't even hear my pump at idle.
    1988 ST165 2.2L @ 370awhp
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  7. #7
    Ultimo Miembro Fantástico Gigantesco Mike431635 is on a distinguished road Mike431635's Avatar

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    This may sound dumb.. but if you can't use electrical tape in the gas tank, how do you wire it securely?

  8. #8

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    Mike431635, best way is to solder the connection and use heatshrink tubing on it, or just crimp the wires with the connectors they give you in the install kit.

    i have the fuel pump relay wired in, but dont have the resistor pack in there. i was thinking about wiring the resistor back in, but i remember reading something about it being better not to have that with the supra pump. even at full 12v, you cant hear the supra pump at all.
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  9. #9
    Ultimo Miembro Fantástico Gigantesco ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD's Avatar
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    Quote Originally Posted by Lagos
    Mike431635, best way is to solder the connection and use heatshrink tubing on it, or just crimp the wires with the connectors they give you in the install kit.

    i have the fuel pump relay wired in, but dont have the resistor pack in there. i was thinking about wiring the resistor back in, but i remember reading something about it being better not to have that with the supra pump. even at full 12v, you cant hear the supra pump at all.
    Your pump would have been much quieter with the resistor wired in. But it was a good thing you looked inside the tank in your case, that was a good catch.

    I'm not denying that the supra pump is quieter, just that the walbro pump is also quiet when wired in properly.
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  10. #10

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    on a realated question... on my supra pump, the electrical connections are just 2 threaded rods that stick out. is it safe to have them exposed in the tank? there is no way they can touch eachother or any other metal part. i mean, electicity cant jump across gasoline, right?

    ive had no problems with it since i installed it a few months back, just being paranoid about anything that has to do with fuel .


    lets move this to the archive at some point. its got good good info for people to refer to .
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  11. #11
    Ultimo Miembro Fantástico Gigantesco ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD's Avatar
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    Quote Originally Posted by Lagos
    on a realated question... on my supra pump, the electrical connections are just 2 threaded rods that stick out. is it safe to have them exposed in the tank? there is no way they can touch eachother or any other metal part. i mean, electicity cant jump across gasoline, right?

    ive had no problems with it since i installed it a few months back, just being paranoid about anything that has to do with fuel .


    lets move this to the archive at some point. its got good good info for people to refer to .
    Nope, the open metal should be just fine in the fuel. It wont conduct electricity.

    Sure we can move it to the archives sometime.

    Quote Originally Posted by nuclearhappines
    The reason people do the fuel relay mod (according to alltrac.net) is that toyota for some reason put a 'break before make' relay in there. So that it breaks the low voltage (resistored) connection to the pump before making the 12 volt connection.

    Most manufactures would switch in 12v first, then disconnect the lower voltage line.

    The way toyota does it, your fuel pump actually gets no power for a split second and starts winding down. (again this is all according to alltrac.net).

    Their suggested solution has to do with wiring up the relay so that it is still in the circuit but the connection is not broken ....

    This problem has dynoed 5hp in the around the fuel pump relay switchover rpm and i saw the dyno (again on alltrac.net)...but this is about 3 years back.

    -nuke
    Yeah those 5hp gains were claimed a long time ago by Adrian Broughton, the old owner of gtfour.com. He did them on the street dyno program. Accurate to a point, but not my preferred way to test for gains especially that small.

    The thing is, a milliseconds worth of the fuel pump not pumping is not going to drop fuel pressure at all. Fuel will still go into your engine, and your A/F will be whatever it is. If you have tuned for a specific A/F ratio, which is consistent across the board, there should be no problem. Also remember your FPR should take care of things.

    One last thing that I dont like about the 5hp gain is that the stock 3SGTE runs so incredibly rich at the power levels he was talking about. He had a 25% correction factor and was making ~275bhp. So thats what, 220whp? He'd be off the charts rich. Giving the fuel pump more power isn't going to do much for you!

    Quote Originally Posted by G-man
    Interestingly, my walbro only makes noise very rarely. I can think of two or three times in the last month that it happened. One was on a relatively warm day when I pulled up to a drive through and idled for a while - it just kept getting worse. Any thoughts on intermittent noise?
    Not sure. How is your setup wired in? Hard to say, but it doesn't sound normal.

    Quote Originally Posted by Todd
    can you explain why it is loud in my car though?
    i havent messed with any wiring/resistors...i just put it in place of the stock pump and it is loud as hell.
    is the 5sfe wiring different? if not, then why is it still this loud?
    Todd, yeah the 5sfe (and 4afe) pumps receive 12V constantly. There is no fuel pump resistor in your case. Here's the diagram for yours: http://www.celicatech.com/93rmsour/1...i/fuelpump.pdf

    Quote Originally Posted by Trance4c
    Does it all really matter that much? If you are worried about 'noise', you should have never done a 3S-GTE swap to begin with. Just my 2 cents.
    baha. preach on. But still, the walbro pump is pretty damn loud. I'm just saying if someone is going to complain about it, they should first figure out if they have their wiring right.
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  12. #12
    Ultimo Miembro Fantástico Gigantesco ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD's Avatar
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    Here is the article from gtfour.com. I can't recover the images.

    I DID NOT WRITE ANY OF THE FOLLOWING:

    Quote Originally Posted by www.gtfour.com
    -------------------------------------------------------------------

    Simple 3S-GTE Fuel Pump Relay Mod - 5hp Free
    Article URL: http://www.gtfour.com/default.asp?article=AAAAHA
    Description: A very quick, simple, free modification to give a bit more power and make power delivery a little smoother in a turbo Celica/MR2
    Keywords: Relay Fuelling Improved Extra Pinging Sluggish Performance 3S-GTE 3SGTE
    Category: Modifications - Engine/ECU
    Submitted: By Webmaster on 7/4/2000 5:12:54 PM, Updated on 3/31/2001 10:18:49 AM

    Who Can Use This Mod?

    The principles discussed in this article should apply to the 3S-GTE motor in general, but I personally can only vouch for it working in my ST185 GT-Four Celica (90-93 model). The instructions shown here are for the ST185, and you will need to find where the "Fuel Pump Relay" is on your vehicle if you do not have an ST185.

    Note also that I have absolutely no idea if this mod is effective on other Toyota motors like the 3S-GE or 5S-FE, but I do know that other ST18x (90-93 non-turbo) series Celicas have a Fan Relay in the location descibed here as holding the Fuel Pump Relay... so don't make any assumptions about this information unless you have a 90-93 model turbo Celica. Note also that the fuse box on my car was rotated 180deg compared to that of another ST185 - so although it is a simple mod make sure you check it all properly - because the effect is reasonably subtle you could think everything went fine and in fact you might have done something like disabled a radiator fan which could end up cooking your motor.

    What Does It Do?

    Having said that, I have found this mod to improve power and smoothness throughout the rev-range, and other people have reported that it eliminated a small amount of pinging (detonation) they were receiving in the middle of the rev-range. The effect is noticable, but I wouldn't say dramatic. Certainly for the effort and cost involved it is one of the first mods I would recommend to anyone.

    The downsides of this mod are slightly higher fuel consumption (you probably won't notice it unless you are fanatical about how much fuel you use, its not much) and it seems to actually make the car less smooth when you are creeping along in traffic under very-low acceleration... it makes it harder to "feather" the throttle to maintain a slow and smooth speed.
    This situation is easy to fix - instead of removing the relay and replacing it with a simple "jumper" as described in this article you leave the relay in its place (very important) and in addition have a switchable jumper that can be controlled from inside the cabin.

    The downsides are so minor that I can't be bothered doing anythinng to fix them in my own car (which I drive every day) - but they are worth mentioning.

    Also this mod will speed up the wear on your fuel pump as it will be operating at full-speed all the time instead of just under full throttle.

    Show Me The Results!


    This chart shows StreetDyno differences of around 5hp across the board at stock boost with and without the fuel pump relay - This is a sample of 6 dyno runs which all showed the same improvements, especially below 5500rpm. The runs were within minutes of each other and this modification was the only difference between them.

    You can see from the chart it gives you a nice torque increase in the 3000-5000rpm range, and this is where you really notice the mod, having felt the difference using my butt-dyno[tm], it was no surprise to see these results.

    If you are wondering about the overall power figures, Yes this was my car running and No I wasn't running a boost controller. I had my boost controller removed from the car at the time so that's why the figures are where they are.

    Where Does It Go?


    (Photo taken from Adrian B's Aus-spec ST185, where fuse box is arranged slightly differently)



    Ok, now the rest of this article is information provided by other people and collated here by me. I have tried to organise it to make it most useful, but prefer to quote it all verbatim than paraphrase it.
    - Adrian Broughton


    Why do this mod?

    > I monitored the Vf output from diagnostics and found
    > (to my horror) that the fuel pump only receives 10.5V under normal driving
    > conditions and switches to 13.5V when flooring it...trouble is, at the point
    > u floor it, the voltage drops from 10.5V to 9.5V and then goes to
    > 13.5V...for a modified car u really need 13.5V at the pump all the
    > time...
    >
    > I think Toyota did this to minimize wear on fuel pump bearings?
    > I found that having changed to 13.5V all the time I never got a "ping" of
    > detonation when flooring it (14psi).

    How to do it?


    >> best way to do it in my opinion is at the fuel pump relay...besides the
    >> low/high voltage fluctuation caused by the resistor pack, there is also the
    >> dead-time that the pump does not run while the relay is clicking. There is a
    >> way to jumper the relay socket and bypass the relay entirely, which also
    >> means it bypasses the resistor pack as well. I did this, with one jumper
    >> wire, and was able to completely remove the relay and resistor.
    >>
    >> Stephen Gunter

    > remove the fuel pump relay, and bridge the terminals. One short piece of the
    > right gauge wire, two male spade connectors, and you are done, literally a 2
    > minute job, and the wire isn't going to stop functioning like a relay could.
    >
    > Regards,
    > John.

    >> The fuel pump relay in the ST165 is located on the rear firewall
    >> behind the inlet manifold and is clearly labelled...

    > The fuel pump relay in the ST185 is located in the second relay box in
    > the engine, the one with the fan and horn relays. On my 1991, US spec ST185 it
    > was a large, bright yellow relay that said "fuel pump" on the side...
    >
    > I made my "jumper" out of a 2.5" length of 10 gauge wire with a male, "spade"
    > connector on each end. Unplug the relay and slide the connectors into the
    > correct sockets.
    >
    > Matt Crawley
    >



    (images above courtesy of Matt Crawley)


    > After jumping the fuel pump relay you can unplug and remove the fuel pump
    > resistor pack located near the coolant overflow tank.

    >> From: "Chris Chin"
    >>
    >> If memory serves, there are TWO resistor packs in the same location. One is
    >> the fuel pump resistor, and this has only two wires. The other is the fuel
    >> injector resistor pack, and it does have a multi-connector with six wires.
    >>
    >> Cheers,
    >>
    >> Chris.


    >>> From Chris Conlon, MR2 list member:
    >>> "I just ran some simple tests on the SW20 fuel pump relay, the one
    >>> that switches the fuel pump between full power and partial power.
    >>> Not too long ago someone had reported that voltage at the fuel pump
    >>> actually dropped off briefly during the switch over transition from
    >>> low to high power.
    >>>
    >>> I wired the relay up as on the car, and hooked it up to the scope.
    >>> Instead of a fuel pump I used a 4ohm non inductive dummy load.
    >>> In the normal position (relay de energized) the fuel pump runs at
    >>> full power. When the relay is energized, the fuel pump is driven
    >>> thru the resistor and runs at reduced power. So the critical
    >>> transition is when the relay turns off, to go from low power to
    >>> high power.
    >>>
    >>> First I tested the relay turning on. This yielded a clean 2msec
    >>> interval with neither connection active. In other words, a full
    >>> 2msec with no power at all flowing to the fuel pump. But, if
    >>> the pump is powering down anyway, maybe this is no big deal.
    >>> Next I tested the relay turning off. This was quite a bit worse,
    >>> the turn off transition was rather noisy, it turned on and off
    >>> a few times before finally staying off. On average I got about
    >>> 2.5-3.0msec of no-power intervals, over a total switch time of
    >>> about 5msec. This off time was typically composed of 2-3 "off"
    >>> intervals of 0.5-1.5msec each, and a few very brief off spikes,
    >>> spread out over a 5.0-5.5msec window.
    >>>
    >>> The relay is a SPDT type, with power applied to the armature. The
    >>> NC (normally closed) terminal goes directly to the fuel pump,
    >>> the NO terminal goes through the fuel pump resistor, then to the
    >>> fuel pump. I do not know why Toyota wired it in this way. I
    >>> personally probably would have used an SPST relay which shorted
    >>> out across the fuel pump resistor. This would still incur the
    >>> switch over time delay, but there would never be a time period
    >>> where the pump is getting no power at all. When I saw the circuit
    >>> layout in the BGB I naturally supposed that Toyota had used a
    >>> make before break relay for this job... but apparently not.
    >>> A simple way to avoid the intervals with no power to the pump,
    >>> while still retaining the function of the relay, is to run a
    >>> wire between relay terminals +B1 and PR, basically the hot side
    >>> of the relay, and the relay side of the fuel pump resistor.
    >>> This ensures that the fuel pump will always get at least low
    >>> power, even while the relay is switching. And since the relay
    >>> does not have a stable "off" position, you're not defeating any
    >>> safety mechanisms. Do make sure to use the +B1 terminal at the
    >>> relay, though, not just any old +12V source, since the circuit
    >>> as a whole is protected by fuses and controlled by a couple
    >>> other relays as well. To bypass these would be defeating safety
    >>> features.
    >>>
    >>> Toyota must not have thought this situation would represent a
    >>> problem (or perhaps it slipped through the cracks), because they
    >>> could easily have used a make-before-break relay, or even simply
    >>> wired it differently so that there would be no drop off even w/o
    >>> a make-before-break unit. (This type of relay ensures that the
    >>> circuit which is being turned on is connected before the one
    >>> going off is disconnected. This results in both circuits being
    >>> connected for a brief period of time during switch over, which
    >>> is usually not desired, and so the average relay is break-
    >>> before-make.)
    >>>
    >>> I did not test the switching latency. I suppose I could but I
    >>> didn't see much of a reason to. Anyone too concerned about that
    >>> had better worry more about when the ECU decides to switch the
    >>> pump to high power, and you're not too far down that path before
    >>> you've set it to run full power full time.
    >>>
    >>> By way of comparison to the "off" time, a single crank rotation
    >>> at 7500 RPM is 8msec, and 2 injectors should start firing within
    >>> that time, 4msec apart. So there is at least some potential for
    >>> there to be a problem, albeit a very very brief one. But, in
    >>> Toyota's defense, the fuel pump has considerable mechanical
    >>> inertia, it's not like it can stop spinning in 5 msec. Also
    >>> there is a check valve in the pump, and maybe if you're lucky
    >>> expansion in the rubber sections of the fuel line will take up
    >>> some slack. If nothing else it does not appear that the relay
    >>> switching itself can be responsible for a second or 2 of issues
    >>> presumably brought on by low fuel pressure. For my part I'd be
    >>> far more likely to suspect either the fuel pump being unable to
    >>> spin up to the new speed promptly, or the fuel pressure regulator
    >>> being a bit slow to close as fuel demand increases suddenly.
    >>> Direct measurement of fuel pressure, with sufficient
    >>> resolution, is probably the easiest way to definitely answer
    >>> some of these concerns."
    >>>

    Credits: Matt C., John B., Stephen G. and Dennis H.
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  13. #13

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    chris i agree, that's what a FPR is for, That's also why some cars have fuel pulsation dampeners (like some hondas, and the mkiv supra) .

    Anyway, I only mentioned it because it was dyno proven, otherwise i would've dismissed it.

    On my vr4 i had my fuel pump hotwired directly to power (constant 14volts).

    My o2's were still cycling at part throttle but at WOT they jumped up from 0.88 to 0.92 which is what i needed. Later on i realised that my flow problem was actually a leaky fuel filter (Which is why i peaked at 0.88volts and was hitting fuel cut alot). But yeah it does richen up your top end. However if you have an SAFC you can easily fix that , and pick up some timing advance (which for the vr4 is a plus).

    depends on the car, depends on the tuning, depends on alot of things.

    -nuke
    2005 C200 Kompressor sport
    K&N Filter, HKS 2.5" throttle pipe, Apexi WS2 Muffler, DIY Voltage Stabilizer, Intrax lowering springs, H&R rear 19mm sway bar, EBC redstuff pads, EBC 13" front rotors, Stop Tech front brake lines, VDO Boost gauge @ 7psi, Greddy Iridium Plugs, Sprintbooster
    On the way:HKS FCD's (12psi), Remus testpipe (2ndary cat), vortech 2:1 FMU

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  14. #14

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    The reason people do the fuel relay mod (according to alltrac.net) is that toyota for some reason put a 'break before make' relay in there. So that it breaks the low voltage (resistored) connection to the pump before making the 12 volt connection.

    Most manufactures would switch in 12v first, then disconnect the lower voltage line.

    The way toyota does it, your fuel pump actually gets no power for a split second and starts winding down. (again this is all according to alltrac.net).

    Their suggested solution has to do with wiring up the relay so that it is still in the circuit but the connection is not broken ....

    This problem has dynoed 5hp in the around the fuel pump relay switchover rpm and i saw the dyno (again on alltrac.net)...but this is about 3 years back.

    -nuke
    2005 C200 Kompressor sport
    K&N Filter, HKS 2.5" throttle pipe, Apexi WS2 Muffler, DIY Voltage Stabilizer, Intrax lowering springs, H&R rear 19mm sway bar, EBC redstuff pads, EBC 13" front rotors, Stop Tech front brake lines, VDO Boost gauge @ 7psi, Greddy Iridium Plugs, Sprintbooster
    On the way:HKS FCD's (12psi), Remus testpipe (2ndary cat), vortech 2:1 FMU

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  15. #15

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    Interestingly, my walbro only makes noise very rarely. I can think of two or three times in the last month that it happened. One was on a relatively warm day when I pulled up to a drive through and idled for a while - it just kept getting worse. Any thoughts on intermittent noise?

  16. #16
    Member Todd is on a distinguished road

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    Arrow

    can you explain why it is loud in my car though?
    i havent messed with any wiring/resistors...i just put it in place of the stock pump and it is loud as hell.
    is the 5sfe wiring different? if not, then why is it still this loud?
    1992 ST-184 Coupe, 5S-FTE
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  17. #17

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    todd, did u use electrical tape when u installed it?


    g-man, thats how my problems started. one day it was quiet, then it got loud. seemed to only happen on warm days.
    Boosted. Tuned. Ready.

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  18. #18
    CelicaTech Supporter Trance4c is a splendid one to behold Trance4c is a splendid one to behold Trance4c is a splendid one to behold Trance4c is a splendid one to behold Trance4c is a splendid one to behold Trance4c is a splendid one to behold Trance4c is a splendid one to behold Trance4c is a splendid one to behold
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    Does it all really matter that much? If you are worried about 'noise', you should have never done a 3S-GTE swap to begin with. Just my 2 cents.

  19. #19

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    im guessing you never owned a walbro, clayton. imagine sitting in your car and hearing a constand EEEEEEEEEEEEEEEEEEE sound. after a few months it will drive you nuts.
    Boosted. Tuned. Ready.

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  20. #20

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    Ok, Todd, you have a 5SFE correct?

    You dont have a relay, your pump puts out much less and it has direct voltage I THINK. If I'm wrong, pls correct me.

    On a 3SGTE theres 2 modes, high and low.

    Question Chris, since you talk about swappers doing this and that to the relay, since I am a native 3SGTE, if I just replaced the stock MR2 pump for the walboro, would i have to do anything special?
    2000 Absolute Red Celica GTS 6-Spd
    1991 Crimson Red MR2 Turbo


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  21. #21
    Ultimo Miembro Fantástico Gigantesco ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD's Avatar
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    Quote Originally Posted by Luni
    Ok, Todd, you have a 5SFE correct?

    You dont have a relay, your pump puts out much less and it has direct voltage I THINK. If I'm wrong, pls correct me.

    On a 3SGTE theres 2 modes, high and low.

    Question Chris, since you talk about swappers doing this and that to the relay, since I am a native 3SGTE, if I just replaced the stock MR2 pump for the walboro, would i have to do anything special?
    You are correct. I posted the link to the 5sfe fuel pump diagram from the BGB that shows this.

    For you, you could just install the fuel pump and it would be nice and quiet. You wouldnt have to do anything special at all. (Just like I did basically...on my "swap", I wired everything to be 100% like stock)
    1988 ST165 2.2L @ 370awhp
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  22. #22

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    same problem here, was making no moise last year, this is making too much noise... I replaces the fuel pump filter, and it change nothing!

    Boris

  23. #23

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    the other thing to consider is that maybe these pumps are not as realiable as people think they are? some supra owners report that louder noise from the walbro is a sign that it might fail soon.

    when mine started to get loud, i tracked down the phone number to walbro and called them. described the problem, and the guy basically laughed and said "yeah our pumps run loud, dont worry about it". i was also sad to find out that they didnt offer a manufacture warrenty.

    someone told me to look into Holley 255 pumps. they are made by walbro but run queit. also the denso supra oem pump is dead silent (i love not having to hear that eeeeeee).
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  24. #24

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    best pumps are oem supra pumps and oem skyline pumps (they outflow the supra pump).

    the skyline pump is a denso pump pushing close to 600hp worth of fuel
    that's what matt from dynamicracing.com uses. He says that pump with a boost-a-pump has outflowed a dual walbro setup on one of his cars... he loves it.

    No one here making that kind of hp though : )

    -nuke
    2005 C200 Kompressor sport
    K&N Filter, HKS 2.5" throttle pipe, Apexi WS2 Muffler, DIY Voltage Stabilizer, Intrax lowering springs, H&R rear 19mm sway bar, EBC redstuff pads, EBC 13" front rotors, Stop Tech front brake lines, VDO Boost gauge @ 7psi, Greddy Iridium Plugs, Sprintbooster
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  25. #25
    Ultimo Miembro Fantástico Gigantesco ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD has much to be proud of ChrisD's Avatar
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    Good info nuke and lagos. Also I would advise everyone to read the post in the above quote by Chris Conlon. Very informative, with real data tests. He comes to some conclusions that I think are fairly reasonable.
    1988 ST165 2.2L @ 370awhp
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