So over this weekend I have been tuning my galant. I am running a single Bosch 044 in tank fuel pump. The pump was working awesome at the 500-550whp range. Once I crested into the 595-600whp range the fuel pump could not keep up. I had to stop at 32psi over the weekend because my car kept going lean at 70% dc on the BlueMax 1350cc injectors

SO the specs.

Single Bosch 044 intank
Not Rewired
-6 an Fuel Line
All -6 from the pump to the rail.

So my next upgrade will be the Fuel Pump Rewire kit, and I would guess that will give me another 50whp or so. But for anyone looking into the limits of the intake 044 there you have it.

If anyone else has personal exp they would like to share I am all ears.



UPDATE:
So I did the fuel pump rewire kit and wow did it boost performance. I have been pulling fuel out of my map like it was going out of style. I am now at 35psi, and the pump is still working strong. I am hopoing to be 40psi on Q16 this weekend. The next thing I will try are the real world limits on E85 and this pump.

So Non Rewire Intank 044 = ~600 dynojet WHP
Rewire Intank 044 = ~675 dynojet WHP so far, still need to dail up the boost.

E85 Info:
Rewire Intank 044(42psi base) = 678whp dynojet. Pump was maxed out and started to go lean.

Are you running the stock sending unit? The 5/16" line that pokes through the top of the unit, has another tube inside it. That leaves about an 1/8" ID for the fuel to flow.

I'm helping a friend build a 1g, and we went crazy and installed -an8 lines to and from the tank, and a bosch 040 intank. Its rated at the same flow capacity as the 044, but it's said to produce 92psi instead if 72psi. We're hoping we don't have the same issue.

I wonder if 32psi boost is reaching the pressure limit for the 044. If your base pressure is 37, +32 psi boost,= 71psi fuel pressure.

Base fuel pressures set at 42psi.

I could see the pump falling off after about 26psi or so. On my map I had to add more duty cycle to keep the motor from running lean.

Good info, I might run a 040 intank and use the 044 as a true inline.

The lack of a rewire is killing the pump performance I believe. IIRC the 044 draws more power than a 255 so the rewire is even more important.

Especially at your higher boost/fuel pressures where current draw goes up quite a bit.

aero_sallee said:

The lack of a rewire is killing the pump performance I believe. IIRC the 044 draws more power than a 255 so the rewire is even more important.

Especially at your higher boost/fuel pressures where current draw goes up quite a bit.

Click to expand...

Also a valid point. I've tested voltage at the pump before and after, and a rewire is important.

IIRC the Bosch 044 and 040 draw 25 amps, which is a lot. Definately rewire it with at least 10 gage. Compare that to the stock pump at 6-8 amps, Walbro 255hp 8-11 amps, Denso 280lph Supra pump 17-21 amps.
source RRE Instructions

pneumo said:

IIRC the Bosch 044 and 040 draw 25 amps, which is a lot. Definately rewire it with at least 10 gage. Compare that to the stock pump at 6-8 amps, Walbro 255hp 8-11 amps, Denso 280lph Supra pump 17-21 amps.
source RRE Instructions

Click to expand...

15.5A at 75psi


A bosch AND a walbro 255 will only draw 22 amps at 60 psi (base pressure + 17 psi of boost) COMBINED.

Please don't give false information w/o researching your numbers.

I run a single bosch 044 external pulling from the tank about 1.5 foot away. Its rewired. I am also using -6 for feed and -6 for return. I have not seen the limits of the 044 yet. And my average times for last year were 10.4X @ 142mph. 3250lb race weight. I unfortunately had to take my car down because my 1150cc injectors were @ 118% duty cycle @ 31psi running a nice flat 12.9:1 AFR. I guess my next injector will be the bluemax 1450cc. I Hope this helps you a little.

Boosted98gsx said:

15.5A at 75psi


A bosch AND a walbro 255 will only draw 22 amps at 60 psi (base pressure + 17 psi of boost) COMBINED.

Please don't give false information w/o researching your numbers.

Click to expand...

How is his post false information? If hese pumps are both capable of pulling 20+amps of power. He never said it would draw that amperage at idle.

Don't be so quick to play the "false information" post. Its rude, especially when its unnecessary. His numbers are consistent with the link he posted RRE Instructions

which comes from a reputable vendor, who I trust more than you. He did his research, you are just being rude.

You NEED to rewire that pump. The pump cannot keep up at that pressure with only 10-11 volts. Depending were your battery is (trunk or engine) you should be running a 10awg power and ground. The pumps will support much more power than what you are making, the rewire WILL fix your problem.

Yes I agree about the rewire. I think that for anyone who thinks you need to rewire your pump to support 500hp you are wrong. I made it all the way to 600 with out a rewire.

I am pretty impressed that this pump made it this far.

So for anyone what just wants to drop a pump in the tank you can and still support tons of power. I will have my rewire done this week and more testing this weekend and will report more info.

I havent run out of fuel yet. Thats because im running two. running them both outside the tank. i have two -6 lines from the pump to a block then it goes to -8 from the block to the rail.

It varies between cars and set-ups, can't tell you why...The Bosch 044 is very capable. The only example I remeber is from a member here and on Talk, whose name is diambo 4 life...

He ran 10.5@like 136 and this was on stock fuel lines Bosch 044/in-tank/ and E-85. 3200lbs weight. Theoretically this means, that he was making MID 600's WHP. Remember that was on E-85, so therefore requires around 30% more fuel...

Colt4G63 also said:

I wonder if 32psi boost is reaching the pressure limit for the 044. If your base pressure is 37, +32 psi boost,= 71psi fuel pressure.

Click to expand...

It shouldn't be. My fuel pressure has been as high as 86 psi on the 044 pump. Although, I run two pumps in series, so my flow doesn't fall off quite a bad as a single pump ran at high pressure.

Just some interesting info. I realize were not talking about ID injectors here, but it can give you a good idea.

If you want to run the fuel pump at its fullest capacity, lower the base fuel pressure. I wouldnt think twice about doing this in your situation Theboz, specially considering your only at 70% duty cycle at an already 42psi base pressure. Lower the base pressure, let the injector duty cycle go higher, and give the pump more capacity to push fuel at a lower pressure. Id say try running a 37psi base pressure and see where your at from there, and adjust accordingly.

I just updated the post with my real world findings on this pump.

Basicly 675 dynojet WHP at 35psi and still plenty of pump left.

I just updated the pump info.

I got back from they dyno today, and at 678hp car started to lean out up in the top. So I am out of pump on E85.

So a single 044 intank and rewired will support 650-700whp.

^^^ Good job Boz...
I think, that what the pump is rated at: Around 700hp.....

Great numbers, man.

andy4g63 said:

It varies between cars and set-ups, can't tell you why...The Bosch 044 is very capable. The only example I remeber is from a member here and on Talk, whose name is diambo 4 life...

He ran 10.5@like 136 and this was on stock fuel lines Bosch 044/in-tank/ and E-85. 3200lbs weight. Theoretically this means, that he was making MID 600's WHP. Remember that was on E-85, so therefore requires around 30% more fuel...

Click to expand...

That would be me. Just to clarify, I went 10.72@138mph with the SINGLE Bosch 044, rewired intank. (my 10.56 was with the additional inline 255 in place) This was also done with stock fuel lines and on E85. My car weighed close to 3200lbs with me in it. I don't believe for a second that 700whp is the max you can make with a Bosch 044 on gasoline considering my car's making close to that on E85.


PS: My setup was with 1600cc/m injectors with the stock fpr in place so 37psi bfp.


Congrats on the numbers!

^^^ Thanks for chiming in...
I am allways giving your case as an example/if you don't mind/, cause you had excellent results...

Running E85 with 1600cc injectors 43psi base fuel pressure and no lower than 13.4 volts. At 32psi with a rewired supra pump and rewired inline Bosch 044 i'm at 94% idc with a .84 a/r housing. I just went up to a 1.0 a/r housing. I'm not really good with fuel calculations etc but i'm sure i'm out of pump. Can someone help me estimate how much power may I be putting down?

Now I will run a inline 044 intank. Does anyone have any idea or know the HP limits of running a rewired inline Bosch 044 intank and a rewired inline Bosch 044?

spoolin ddub said:

Running E85 with 1600cc injectors 43psi base fuel pressure and no lower than 13.4 volts. At 32psi with a rewired supra pump and rewired inline Bosch 044 i'm at 94% idc with a .84 a/r housing. I just went up to a 1.0 a/r housing. I'm not really good with fuel calculations etc but i'm sure i'm out of pump. Can someone help me estimate how much power may I be putting down?

Now I will run a inline 044 intank. Does anyone have any idea or know the HP limits of running a rewired inline Bosch 044 intank and a rewired inline Bosch 044?

Click to expand...

What makes you think you're out of pump? Are you dipping lean?

I'm at 101% IDC on my 1200's running the exact same fuel pump configuration as you, and I know I'm not out of pump. But, I don't have any experience with E85 either...

Got a log?

spoolin ddub said:

Running E85 with 1600cc injectors 43psi base fuel pressure and no lower than 13.4 volts. At 32psi with a rewired supra pump and rewired inline Bosch 044 i'm at 94% idc with a .84 a/r housing. I just went up to a 1.0 a/r housing. I'm not really good with fuel calculations etc but i'm sure i'm out of pump. Can someone help me estimate how much power may I be putting down?

Now I will run a inline 044 intank. Does anyone have any idea or know the HP limits of running a rewired inline Bosch 044 intank and a rewired inline Bosch 044?

Click to expand...

What turbo? Engine size?