My walbro is going out ( I think... ). Its starting to make a super high pitch whine all the time now and just sounds like its getting ready to die. I read on the mitat forum that the walbros theyve been using dont usually last more than a year, and are known to whine really loud right before they fail. Well, since one of the last things I want is a fuel pump failure, I decided Id just replace it anyways. Now...My questions are,





Is it true walbros dont last much longer than a year ( thats about how much time is on this one... )?



and



If it is true, what other pump should I use and where should I get it?

Has yours been whining since the installation of your haltech? Mine has. Can anybody substantiate this possible problem?

It was whining higer than normal, but I attributed it to the fact that it was directly wired now instead of going through the ECU. I know that the stock ECU would drop voltage to the fuel pump 30~45 seconds after startup. After the E6K install, it was just whining as loud as it always did right after startup.



But now it sounds like a transformer. You can hear it from behind my car over my exhaust. Very noticable. Very high pitch. Very loud.

damn, i'm fixing to buy a walbro, i hope we can get some answers because i want to save a headache https://www.nopistons.com/forums/pub...1047683358.gif

I have one right now, getting another... I hope this isn't true.. bump^^

switch to a bosch motorsport pump

Whats the +'s of switching to that?

very high flow pump and very reliable. they are costly but you can run them in the tank with some modification. its popular on FD's

oooo i will have to eventually need to do a fuel pump mod... goood topic... keep talking

how much does that bosch flow???

You need to match the fuel pump to the application, such as if your going with 4 x 1000cc your gonna need more than one fuel pump, for example KSP engineering uses a Skyline GT-R fuel pump to fill a catch chamber then has twin Bosch 044 pumps feeding 4x1000 and 2 720cc sub injectors, I will be going with an aeromotive A1000 or twin walbros for my setup which will have 4x 1000cc injectors, For Beau's 20b he uses twin Aeromotive A1000's with 6 x 1680cc.



here is a pic of KSP's Drag FC https://www.nopistons.com/forums/pub...1047683894.gif https://www.nopistons.com/forums/pub...IR#>/bigok.gif



http://www.ksp-drag.com/fc3s/car/UPDIARY/19.jpeg





althought this may seem like a lot of overkill, believe me you do not want to find out you do not have too small of a fuel pump.

Holy ****, can you go into more detail about that fuel setup, I don't understand it all... https://www.nopistons.com/forums/pub...1047683561.gif

That setup looks similar to an idea i had..





revvin, i believe that they have a single larger(higher flow)pump that fills a smaller "gas can" or catch can then uses dual smaller pumps to draw from that, this allows fuel to be added to the catch can quicker then the dual pumps can draw it out. This way, the two smaller pumps are never starved...and neither is your engine...



correct me if i'm wrong...

I dont understand...If the one huge pump can put gas in faster than the small pumps can take it out, why dont you just run the single huge pump to your engine?... https://www.nopistons.com/forums/pub...IR#>/dunno.gif





But to be back on topic, is it true that Walbros are known to fail? Or is it just a nasty rumor?

How much HP is the Walbro good for anyways?

Adam I"m still not sure if there are any problems with the Walbro, but I just learned something interesting from Chris Ott at Rotary Performance. He recomends supplementing the ground for the pump. He said to just pull away some of the insulation around the wire and sodder(sp) another wire to it and ground it to the chasis. I'm going to do this in the next couple of days. I'll let you know if it quiets the pump down any.

Fuel starvation. That little intermediate tank is always full and fuel can't slosh away from the pump pickup like in the big tank. You can therefore run less fuel in the main tank without worrying about your fuel pumps not being able to send a constant supply to the engine.



Have you ever gone around a corner with the fuel needle on "E"? If you're really low you might get a few stutters and jerks because your fuel system just ran dry. Once you finished the corner the fuel flowed back into a position where the pickup could reach it. Now just imagine doing that at 20 PSI coming at of a corner onto the back straight. https://www.nopistons.com/forums/pub..._DIR#>/sad.png

BTW, you really don't need a "huge" pump to fill that can. Since it is not pressurized, a small pump can keep up with the 2 larger pumps feeding the injectors.



And that fuel setup in the picture is so far from legal in North American racing it's not even funny. https://www.nopistons.com/forums/pub...#>/biggrin.png Very purty though https://www.nopistons.com/forums/pub...1047683827.gif

Since I wired up the haltech, I did ground the pump to the chasis.

Fuel starvation. That little intermediate tank is always full and fuel can't slosh away from the pump pickup like in the big tank. You can therefore run less fuel in the main tank without worrying about your fuel pumps not being able to send a constant supply to the engine.



Have you ever gone around a corner with the fuel needle on "E"? If you're really low you might get a few stutters and jerks because your fuel system just ran dry. Once you finished the corner the fuel flowed back into a position where the pickup could reach it. Now just imagine doing that at 20 PSI coming at of a corner onto the back straight. https://www.nopistons.com/forums/pub..._DIR#>/sad.png [/quote]

I see. Thanks for the info.

what is in the spare well?

I am not quite sure of what is in the spare tire well, I believe it may be a cooler of some sort.



As far as the KSP setup, they run the GTR fuel pump (240 lph) into the catch can and the 2 Bosch pumps (280 lph each) feed the engine. The reason they go this route is that the bosch pumps flow more than the GTR pump, but they are external pumps, whereas the GT-R pump is internal. In order not to have to run a fuel cell in the car they run this.

So does anyone know how much power the Walbro 255lph HP is good for?







Also, something I didnt understand is that people said you need a fuel pump bigger than a walbro if youre using 4x1000cc injectors...

Well...Thats 4 liters per minute, which comes out to 240 liters per hour. If the walbro pushes 255 liters per hour, why do you need a different pump for those injectors?













P.S. Ive read on few places online that the Walbro 255lph HP is good for 90psi and 550hp...Any truth to this?

The Walbro is rated at 255lph @ 45 psi of fuel. Now bumping that to 90psi is not a good thing. One of the guys asked why there pump got louder when they installed the engine management system. This is because most Engine management systems require you to run a relay to the pump instead of the factory computer controlling the pump. Well in the factory ECU's the ground is controlled by the ECU for the fuel pump and will not go into a high flow rate until the ECU commands it to, by giving the pump a relay and a full ground you are at max output of the pump at all times hence the pump being louder.



I personally would not mind having a pump rated a lot higher than the rated output of the injectors for the circulation value. For each person it is different. I prefer overkill rather than what might get me by in a pinch.

or you can just get a sump like i have no more fuel slosh https://www.nopistons.com/forums/pub...#>/biggrin.png

pixs https://www.nopistons.com/forums/pub...IR#>/smile.png ?

that cooler in the spare tire well most likley is the differential oil cooler. a neat trick for going FAST. MCR in japan uses that on the skylines they build.

how would it cool if it's in the tire well?

it just gets the heat out of the diff

Great post so far. It has answered many of my questions. I am in need of a new fuel pump since the factory likes to lean me out before 15 psi https://www.nopistons.com/forums/pub...O_DIR#>/11.gif .



So Camel, are you saying that if you bypass the ECU's ground to the pump and instead ground the pump to the chasiss, you can trick the pump in to pumping more fuel or just full pumping all the time??



I've seen those little fuel pump rewire kits, do they just replace the ground wire then or what??

Does anyone know how much power the pump is good for?..

Is the 550hp number right?

This is a common trick in Japan, but I would not reccemend doing this unless you have a fuel pressure regualtor. Essentially the pumps rating is at a specific output, lets say 255 liters per hour @ 45 psi 13.7v DC . Now the average charging system is normally 13.7 v DC when output is not being eaten by fans, headlights etc.



Most manufactuers know you will not need to have all that pressure on a stock motor @ idle. So a variable ground system is incorporated into the ECU and output of the fuel pump is changed according to load. This is fine for a stock motor and fuel system, but when you add larger injectors you run the risk of a lean condition in the few seconds it takes the pump to go from a low output to a full output. Think of it this way, the popular upgrade to a TII or FD is to put 1000cc or 1600cc in the secondaries. If you go full throttle and the fuel pump is in low output, how fast are the injectors going to dump fuel in comparison to the pump trying to get to full output? I will try to get everything in order on wiring schematics and voltages so I have a more educated answer on doing a full output in comparison to the stock ECU output to the fuel pump soon. But I have seen the proof in a few of the cars here. One being a Nissan Skyline R31 w/ RB26 swap T-88 Turbo, 280 cams, 2.7 bore up and many other performance mods. The car had 720cc injectors installed and was litterally going lean on the top end because the ECU could not get the pumps up to full output fast enough. The car had twin GT-R fuel pumps feeding a single line. The owner of the car used the ECU's pump 12v + feed wire output from the ECU to turn a Bosch relay on to power the pumps and grounded the pumps to the chassis of the car and has not had a problem since. I am still trying to decide which fuel pump(s) I will run, I am looking at 2 options, one is twin Walbro in tank pumps similar to the Skyline listed above and the Blue FC here in Okinawa, the other is to remove the stock fuel tank and have a deep sump welded to the bottom of the stock tank and run a single Aeromotive A1000 under the car w/ new fuel lines to the engine bay in either case. Since this will be a weekend drag racer, and a daily driver through the week I am trying to keep as much hatch space as possible by keeping the stock fuel tank and not going to a fuel cell

?....

Its more than enough for your current setup I'll tell you that..



I forgot the specifics but I though it was good for about 500hp.

i've seen 400rwhp on a walbro

Well no duh https://www.nopistons.com/forums/pub...IR#>/wacko.png



I dont ever plan on making much past 350~400 so I just want to make sure the Walbro can get me there.

Well no duh https://www.nopistons.com/forums/pub...IR#>/wacko.png



I dont ever plan on making much past 350~400 so I just want to make sure the Walbro can get me there. [/quote]

https://www.nopistons.com/forums/pub...#>/biggrin.png hehe

I have the same pumps as KSP Drag has....They work really awesome.... I had two pumps as well but didn't find myself needing the inline and now just run the intank only.

did you have your car on ebay a couple days ago?

NO.... I think there is an N/A with a silver paint job running around....Mine is far from an N/A https://www.nopistons.com/forums/pub...IR#>/smile.png