Fuel pumps. Calculate fuel requirements walbro pump 255lph 255 from a QX56.....

[Nowhere]

I have access to stock QX56 315HP intank fuel pumps. Based on this calculator:http://www.z28.com/calc.htmlthe qx pump pumps out 26.25 gallons per hour at 100% (Not sure if Nissan/Infiniti has any buffer in there...).The infamous walbro unit flows 67 gallons per hour or the "255" liters per hour.

Could it be said a QX56 intank fuel pump would provide sufficent fuel flow for a CA18det stock/light mods/MODS/race engine??

The qx56 service manual notes 51 psi at idle.....

Sounds like a good subsitute for the wolbro 100 dollar unit?

Would a nismo/adjustable fpr be required??

[mbmbmb23]

How much would you be spending on the QX56 unit? Reason I ask is that you can get an "un branded" Walbro for like $70 shipped on ebay:http://cgi.ebay.com/ebaymotors...%3AIT

-m

[Nowhere]

The qx56 pumps are free They don't have a sock if memory serves..

[mbmbmb23]

Well....if they are free you could always run 2 of them side by side like people do with Walbros and use a Nismo FPR.

-m

[Jezz_s13]

if you can get other hand me down nissan pumps then the Z32 TT pump is a very good pump.

at least as good as the walbro 341 and 342.

[81na ZX]

fuel requirements are due to injector size and duty cycle, obviously.

80% Duty CycleInjector - lph - gph450 - 86 - 22.8550 - 105 - 27.8660 - 126 - 33.4720 - 138 - 36.5

100% Duty Cycle (a safer estimate)Inj - lph - gph370 - 89 - 23.4450 - 108 - 28.5550 - 132 - 34.8660 - 158 - 41.8720 - 173 - 45.6

So, if your right about the QX pump pumping 26 gph, it wouldn't be safe to run it on any modded motor. It "fine" for a 100% stock motor though. No room for improvement though. And a 255lph will be safe for 720 wide open all the time. Not safe for the injectors or engine, but safe for the pump

Anytime you run a big pump, its safest to use an afpr.

[Nowhere]

fuel requirements are due to injector size and duty cycle, obviously.

80% Duty CycleInjector - lph - gph450 - 86 - 22.8550 - 105 - 27.8660 - 126 - 33.4720 - 138 - 36.5

100% Duty Cycle (a safer estimate)Inj - lph - gph370 - 89 - 23.4450 - 108 - 28.5550 - 132 - 34.8660 - 158 - 41.8720 - 173 - 45.6

So, if your right about the QX pump pumping 26 gph, it wouldn't be safe to run it on any modded motor. It "fine" for a 100% stock motor though. No room for improvement though. And a 255lph will be safe for 720 wide open all the time. Not safe for the injectors or engine, but safe for the pump

Anytime you run a big pump, its safest to use an afpr.

Hmm, the above CC to Lph/gph numbers are for FOUR injectors correct? The ##'s would be doubled as the QX is a v8..With injector cc calculators, seems the qx56 has 240cc injectors.240cc at 51 psi = good fuel pump for ca engine?Hmph... I need to find the CC for the injectors on the QX to make a better assesment.Wonder if the fuel pumps will have a p/n that will correspond to the performance specs on the pump..

[Nowhere]

ok, it's a Denso 195130-9200 pump..The 195130 series of pump goes from 90lph to almost 300 lph.....I can't find any info on this pump! ARR!

Wonder how easy it would be to test this pump's flow rates...

[81na ZX]

Thats not too hard If you have a graduated cylinder of some kind.Just run the pump on 14.4V for like 5 or 10 seconds and see how much it fills up

[c-rad]

Thats not too hard If you have a graduated cylinder of some kind.Just run the pump on 14.4V for like 5 or 10 seconds and see how much it fills up

That will still just give you an estimate. Voltage is directly related to flow. If you are giving it the full14v then it will be higher since the pump probably only gets about 12v due to the crappy stock wiring. But then again, I am sure its pretty easy to just hook up a 12v car battery. This post is pointless now but I made the effort to get this far so I am posting it anyway.

[knightrider]

if you do use the qx fuel pump, it will flow less because the ca runs at 3 bar, which is 43psi, not 51psi, they are acheiving the flow needed for the qx by raising the fuel presure.

[Nowhere]

if you do use the qx fuel pump, it will flow less because the ca runs at 3 bar, which is 43psi, not 51psi, they are acheiving the flow needed for the qx by raising the fuel presure.

Uhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh,hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh,

Ok, so lowering the pressure (the ca setup) vs. the higher pressure setup (qx56) would LOWER THE FUEL VOLUME/FLOW?

Uhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh,hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh,no..

Unless you're refering to the injector flow rates... Example, QX56 injectors at 3 bar would flow less than they would at the 51 psi (meaningless, QX injectors are irrilevent to this post, except to estimate the pumps flow rates, which would be greater at the CA setup as it's got LOWER fuel pressure..).

[Nowhere]

If I were to find the stock QX56 injector CC rating, I could calculate the fuel pump LB/hr... Could it be said that the QX should/does impliment an 80% injector duty cycle?? If so, 100% cc - 20% cc x 8 injectors = total cc/min rating...

[cortina-mk1]

more info you ...

Std GTST pump is 135 litres per hour and supports 300 bhp at standard pressure Std GTR pump is 190 litres per hour and supports 420 bhp at standard pressure Bosch 910 pump is 200 litres per hour and supports 450 bhp at 73.5 PSI # 0 580 254 910 Bosch 975 pump is 228 litres per hour and supports 500 bhp at 73.5 PSI # 0 580 254 975 Bosch 984 pump is 228 litres per hour and supports 500 bhp at 73.5 PSI # 0 580 254 984 Bosch 040 pump is 235 litres per hour and supports 520 bhp at 73.5 PSI # 0 580 254 040 Bosch 044 pump is 330 litres per hour and supports 730 bhp at 73.5 PSI # 0 580 254 044

[81na ZX]

That will still just give you an estimate. Voltage is directly related to flow. If you are giving it the full14v then it will be higher since the pump probably only gets about 12v due to the crappy stock wiring. But then again, I am sure its pretty easy to just hook up a 12v car battery. This post is pointless now but I made the effort to get this far so I am posting it anyway.

Well ya, but so does using a stopwatch or clock to time when to connect and disconnect the power Lots of tiny variables, but still an estimate to know if its too small.

[slownslurious]

the stock pump works fine on a stock swap, when my wastegate line was messed up I was running 15 psi on the stock (ka) fuel pump... I'm not saying its a good idea.How could the QX pump not be large enough when the damn thing has a giant v8 that makes way more power, and its fpr is set higher?? flow rate should increase as pressure decreases so whatever its capable of flowing on the QX, it should be capable of more on a ca18...

[jjwilks240]

i was runing 10psi daily on my ca with stock pump, with fmic, sr turbine, full3ini had no problems, i have walburo pump now though

[81na ZX]

the stock pump works fine on a stock swap, when my wastegate line was messed up I was running 15 psi on the stock (ka) fuel pump... I'm not saying its a good idea.How could the QX pump not be large enough when the damn thing has a giant v8 that makes way more power, and its fpr is set higher?? flow rate should increase as pressure decreases so whatever its capable of flowing on the QX, it should be capable of more on a ca18...

Quote »i was runing 10psi daily on my ca with stock pump, with fmic, sr turbine, full3ini had no problems, i have walburo pump now though[/quote]Were these done in 240's?

This swap is being done in a Suzuki, not a nissan.

[slownslurious]

does it matter? a ca is a ca, I'm not sure why what vehicle its going in would make a difference, especially since you'll have to run wiring to whatever pump you decide to use, which gives you the oppurtunity to use 8 or 10 gauge so it will see a few extra volts over stock.

[biosehnsucht]

it matters if "stock pump" in a 240 is different from "stock pump" in a suzuki

[float_6969]

fuel is fuel, and horsepower is horsepower. It is going to take x fuel + y air = z horsepower. It's as simple as that. It's all based on volume. It doesn't matter if you're using a 1.8L to make 300hp or a 5.6L to make 300hp. It's still going to take about the same amount of fuel to do it. There are of course all sorts of variables, but they aren't going to be that far off from each other. End of story.

My vote: As long as you aren't planning on exceeding the lower 300hp range, the QX56 fuel pump should work just fine with the CA18.

[slownslurious]

it matters if "stock pump" in a 240 is different from "stock pump" in a suzuki

Thats why I said my KA pump, since that narrows it down, if only slightly (for instance, defintley not a stock suzuki pump).

I have to agree with float here, he said what I was trying to above (about HP and pressure = x fuel no matter what engine.

[81na ZX]

But its not quite that simple.

A Good NA engine has a BSFC of 0.50. It uses 0.50 lbs of fuel per hour for each horsepower it produces. A Poorly tuned FI engine has a BSFC of 0.65, and we all know stock FI computers are wicked rich. Thats about 30% more fuel per hour for a poorly tuned FI engine over a good NA engine. (0.15 is 30% of 0.50 right).

Now a well tuned FI engine can have a BSFC of about 0.60, that makes the fuel draw less.

Concievably, a 300hp CA will require as much fuel as a 430 hp NA engine.

[Nowhere]

it matters if "stock pump" in a 240 is different from "stock pump" in a suzuki

Correct As I have a front clip (if you're following my insane posts ), the CA pump is not available.. The 240 pump would cost me money (cheap bastard ), the QX pump is a "FREEEEEEEEEEBIE, ZIP, ZERO, ZILCH" (monster garage..)..

I'm going to assume the stock suzuki pump is just NOT an option to use with the CA engine.. Should I do a simple flow test on the QX pump?Should I just shut up and buy a walbro and a nismo/adjustable FPR (hehe)?Should I go with the QX pump and the above regulator option and a fuel pressure GAUGE (to see what she's doing under high power)??

Options, Options, Options, Options, Options...

THANKS TO ALL FOR THEIR INPUT!!!!!!!!!!!!!!!!!!!!!

[slownslurious]

I have a stock 240 sender and two stock 240 pumps I would be willing to part with very cheaply if you want, since I know one of them is good for a stock CA I'm sure two of them would be even better for a tuned one.

[float_6969]

But its not quite that simple.

A Good NA engine has a BSFC of 0.50. It uses 0.50 lbs of fuel per hour for each horsepower it produces. A Poorly tuned FI engine has a BSFC of 0.65, and we all know stock FI computers are wicked rich. Thats about 30% more fuel per hour for a poorly tuned FI engine over a good NA engine. (0.15 is 30% of 0.50 right).

Now a well tuned FI engine can have a BSFC of about 0.60, that makes the fuel draw less.

Concievably, a 300hp CA will require as much fuel as a 430 hp NA engine.

As I said in my post, there are many variables here that could be used to make the example that you did, but for the original posters application, I think that the extremes that you are using as examples are accurate but are misleading. I'm not questioning the correctness of your statement, as it's quite true, but we're not dealing with F1 cars, and I don't think we're dealing with a poorly tuned CA either.