Marcel Burkett

As some of you may have read I am now running into problems with fuel , my duty cycles are 88% @ 9000RPM and 15psi boost , the A1000 starts dropping pressure as the rpm's go up. I was looking at replacing it (the A1000) with a pair of BOSCH 044's but after looking aroud I have found that they are a bit pricy ( I am fed up spending and the holidays are here ..... , you know what happens at this time !!) , so I am thinking of a cheaper alternative . I am looking at putting a pair of SUPRA TT or 300ZX TT fuel pumps into my tank , T'ing them into the supply line and having the E6K start them when required , used items like those are fairly cheap down here , what y'll think is that overkill , remember I want to get up to 25-28 psi with the TA51 on a half bridged 13BREW.

680RWHP12A

that sounds like a bad idea...

i went through the same problem!!!
get a weldon 2035 and you will be done , it will work for sure!!!!

ZoomZoom

iTrader: (2)

I would think the pump would be enough. I suggest upgrading your lines to larger diamter lines so more volume can flow through. Even at same pressure as before with stock lines the volume will be sufficient and wont drop pressure as fast.

680RWHP12A

those pumps suck. i had one on my car and i couldnt make more than 500 rwhp with it. the pump pressure falls off as the rpm's go up, wich is a sign the pump cant make enough volume to keep up..
p/s my car has 1/2 inch fuel line too...
i bought the msd fuel pump booster and burned that up, i was told it would work by msd techs but later told it couldnt take the amperage of the pump !!
finally i bought a weldon 2035 and my problems went away!
now i need a 5 bar map sensor!,,,ill let you know if the weldon keeps up at 40+psi of boost

ZoomZoom

iTrader: (2)

Now thats the info you needed. Wow. I was dissapointed in that pump.

Marcel Burkett

But isn't the walbro 2035 $775 ? , thats even more than the pair of BOSCH 044 pumps . Remember that I am looking for a CHEAPER yet EFFECTIVE alternative.

93 R1

Cheaper isn't always better...I'd just hold off till after the holidays and get the expensive ****. That way you know you will be o.k.

No sense in blowing that bad ************ apart to save $200 on a fuel pump....right?

SPOautos

How much base fuel pressure are you running? I'm sure you know this but as the pressure starts to rise the pumps flow starts to drop off. That pump could be intended for a N/A application and make to flow a ton at a low fuel pressure, say 40psi. But then when you get under the boost and the fuel pressure starts to come up the flow might be droping off.

Can you get a flow chart for your pump (some are online) that shows how much flow it has at certain pressures?

Maybe you just need to run a real low fuel pressure.

STEPHEN

SPOautos

Ah Ha, I found your flow chart....

http://216.242.145.16/products/produ...ml?p=3&large=2

If your running a base of 40 plus 15psi of boost plus about 10psi loss in the fuel lines then your pump would be having to produce about 65psi. According to that chart it can flow about 400lbs/hr at 65psi.

What size injectors do you have?

SPOautos

Damn, I hate we cant edit posts after 30 minutes uhh

Anyway, saw your fuel specs in another thread. Your running 6000cc/min of fuel injector at 88%, holy **** man thats a lot of fuel. To sustain fuel pressure and flow at 88%inj duty cycle you need a pump that will flow 82gallons per hour, your current pump at your current pressure level only flows 67 gallons per hour!!! No wonder your running out of fuel.

To sustain 88%inj duty cycle your going to need a pump that can supply 82 gal/hr OR right at 500 lbs/hr at what ever pressure you'd be running. Dont forget that your pump pressure is base pressure, plus boost pressure, plus 5-10psi more cause of line pressure drop. If you wanted to run a base of 37 + 28psi boost + another 10 for drop you'd be at 75psi. To find a pump that would max out your injectors at 28psi of boost means your going to need a pump putput of 93gal/hr or 560lbs/hr

Sounds like you need to be on the hunt for a mamoth pump haha

STEPHEN

SPOautos

Yea, I'm bored at work lol

Here are the flow charts for the Weldon pumps you can get at SR.
http://www.weldonracing.com/pump3.htm

Those are some bad *** pumps right there. Its looks like the Weldon 2015 would do the trick. It seems to fit your needs almost perfect at it flows 100gph @ 75psi. The 2025 gives you a lot of extra room and only cost $40 more than the 2015 so you might want to go that route also.

They are very expensive pumps but running as much injector and fuel needs as you have I dont think there is much alternative if your wanting to run that high of boost.

I know that doesnt really help you with an "economical" solution but if you are maxing out your current pump this is pretty much the next thing to jump to. You'r going to spend so much time and money trying to come up with a bandaid you might as well just bite the bullet and spend a couple hunderd more for the real deal like a Weldon 2015 or 2025.

BTW - How much power are you making? Has it been on the dyno yet?

STEPHEN

in2twins

Marcel, I'm not sure why this is so difficult, Tons of Supra guys are running twin high pressure 255LPH Walbros, and putting 800+rwhp to the ground, even allowing for the slightly richer AF ratios we require I do not buy that these pumps will not do the job. TYson posted a great link to test data on these, and many of the other pumps being discussed here, I will try and find it later, or just search Tysons posts in this section, it was in the last several months. I guess my point is the whole set-up will cost you ~250.00 for the pumps, pigtails, and filters, and is currently supplying plenty of fuel to alot of 800rwhp Supras. The Supra pumps are almost as good, but do not live as long at 12n volts continuous, plus used they cost more than a new Walbro. I will post the link this weekend latest, but I am very sure of my info. Regards, Carl
BTW, they are small enough to pass through the stock opening in the fuel tank when properly bundeled together.
these guys know it all when it comes to these pumps, and they have great pricing. http://www.autoperformanceengineering.com/

SPOautos

in2twins - If you have some flow sheets of 2 Walbros together I'd REALLY like to see it. I was trying to find a flow sheet of that online but couldnt. I was hoping to compare that to a Weldon pump.

Update - I found a flow chart of 2 Walbros but it doesnt look NEAR enough for his fuel system. It would be hard for me to believe people are making 800rwhp on 2 Walbros cause with a base pressure of 40psi, 20psi of boost, and 10psi pressure drop in the lines it would only put out about 65gph of fuel.

http://www.mkiv.com/techarticles/fue.../pump_test.jpg

STEPHEN

in2twins

Here is the link
http://www.stealth316.com/2-fuelpumpguide.htm

SPOautos

With a 50 base pressure running say 20psi of boost on top of that then fuel line losses your pumps putting out about 80-90psi. At 90psi that A1000 puts out 340-350lph (which is 56-58gph). That means that its going to max out at 3700-3800cc's of fuel....which is about 85% duty cycle for your injectors.

Course it all kinda depends on how much boost you run. That A1000's flow drops pretty fast at the pressure gets high. The HP specs and all that for that pump are based on a N/A application running low fuel pressure.

I have a link to the flow chart a few posts up if you want to check it out.

STEPHEN

Godzilla-T78

I have the HKS Racing fuel pump. I never have a problem with it.

Matt

vosko

iTrader: (4)

speed-NYC had a weldon OMFG loudest goddamn thing. i'm sure it pumped alot but the pump was louder than his and exhaust and you could barely hear the wastegate above the noise it is NOT for a street car unless you are insane!

93 R1

Yeah that thing is nuts. With the car at idle, you can hear the fuel pump whining from 50 ft away. No JOKE.

Marcel Burkett

Remember I am talking about keeping the A1000 and using an additional pair of pumps to suppliment the flow .

suganuma

Do you have any cited testing/evidence of the supra pumps not lasting as long at 12V? Approximately what sort of life do they have? Sounds like you've seen this and researched it a lot, but I'd just like to read some first hand experiences and such.

TIA,

Nic

Carl Byck

I have a 97 Supra(and a T66 widebody FC), and I am in the process of doing a T66 single conversion on the Supra. I have spent two years on Supraforums studying up for this conversion (~10K+ cost for the conversion on a car that is 1 of 21 built)). Obviously since I own a Supra pump already, this would be the easiest, and the cheapest way to go. Unfortunately, I have read of quite a few failures of supra pumps in cars with 40k-70k miles(those pumps last over 150,000 ordinarily), where the owner has done what we call "the 12vt mod" basicly bypassing the relay that switches from 9vts(less than WOT), to 12 volts(WOT). This is done on alot of cars which are trying to get the most out of stock fuel which lately has been raised on the dyno to 625rwhp(550 is usual max)@100% duty cycle(side feed injectors) W/RRFPR, 12vt mod and pulsation dampener removed. In a nutshell pumps that ordinarily last 150,000 plus, are failing within 10-20,000 miles after being converted, some sooner, also ther seems to be a fuel heating problem associated(a couple guys had fuel delivery problems while driving to vegas last year) with running these pumps at 12vt continous. They were not designed for that type of operation, and seem to be failing when subjected to it at a higher rate than is ordinary.
So That is what I know, and how I have come to know it. There are also plenty of guys running dual supra pumps without a problem, but since two Walbros cost 50.00 more than a used Supra pump I will be using new dual walbros in my car.
If you would like first hand info do a search on Supraforums, on the 12vt mod, and problems.
Hope this helps, Carl

wonder1and

What I was told to do was hook up another if not replace both of my FP's and since I've gotten rid of the emmisions crap I could use the other hard line that runs down the frame to the charcoal can (after being cleaned REAL WELL!)... then t-them at the fuel rail. I just posted about maxing out my 1600's x2 and 850's x2 @ 14psi... running both down the rail then t-ing them sounds like a good idea to me. Opinions? Also I need to put a bigger battery in... mines to weak!

SPOautos

Does he know if they are all that loud? You have any idea what model Weldon he had?

STEPHEN