I feel like this is just like compound turbos. I dont understand how you can have a tiny turbo feeding a massive turbo and make anymore power then the tiny turbo can flow.

 

I can build a test stand with whatever pump/plumbing scenario(s) we want with the pumps in hand. I would use short lengths of 3/8 fuel injection hose, plumb a coriolis flow meter ($$$$ thank god I have access to alot of them in different flow ranges)...

I will have to see what fluids we have them calibrated for in the anticipated range and then just correct for the fluid we run. I will run a fluid with KNOWN properties such as dodecane (similar to diesel) or heptane (0 octane) or iso-octane (100 octane) or Viscor 16A and 16B (fuel injection calibration fluid I have worked with on previous projects).

I will also throw a high accuracy pressure transducer in upstream AND downstream of the booster pump to see if there is a pressure differential. Will only use 1 pump on the parallel fuel pump setup test obviously.

 

Believe It’s the other way around with compounds. Large turbo feeding smaller. It’s because air is compressible as, Stevie said. You can take all the air molecules in a room and compress them down to a much smaller size. Can’t really take a 20 gallons of fuel and shrink it down to 1 gallon size by pressurizing it. If 1 pump is fed by another though, it won’t have to work as hard. Bad comparison on my part.

 

I'm game... PM sent.

 

I just set my nova up with a booster pump. I have a in tank 450 with a -6 feed (about 2 feet) to a Y then I have a bosch 044 pump that has -6 feed to the y then a -8 length of car to fuel rail. I'm running holley efi so I have the inline pump coming on @ 150kpa.
When I tested the system I noticed the 2nd pump bumped the pressure 5psi when activated

 

Because the big turbo blows through the small turbo. It's feeding it compressed air, so a smaller orifice in this instance is less of an issue because the charge is more dense within that fixed volume.

The same will not apply to liquids.

And that article FF posted does state specifically centrifugal pumps. Any fuel pump I've seen or taken apart are not centrifugal in design. SO I'm sure that will affect any tests.
But the article does also seem to imply in series offers little extra flow, just more pressure ability. In parallel will be double the flow.

It'd be more like feeding a huge turbo into a tiny 112 Roots blower with no bypass ability. At some point the 112 blower will limit power no matter how big a turbo you try and ram air through it.

 

Would be very interesting to see what a series test with say a walbro 450 first boosted by an AEM 380 and then vice versa. Maybe a walbro 450 pump would maintain flow better at higher pressures if it is fed higher pressure fuel to it's inlet vs sucking out of a tank.

It seems the old walbro 255 pumps did great in parallel even at 70-80 psi. Not sure parallel centrifugal walbro 400/450's can perform as well at higher pressures.

Better yet maybe Denmah can do a series test LOL! His two Walbro's would not cut the mustard up at high boost......not sure a booster pump can get him there or not.

 

As far as fuel pump flow versus pressure, there are graphs online for all of the pumps including the 255, 450, 380, 044, etc etc. I will reproduce the single pump flow, then dual parallel, then single with booster in series, and then could do dual in parallel to a single booster (although I think the single booster may be a restriction...although its getting pressurized feed, and not having to lift the fluid.

 

A lot of the intank pumps have internal bypass/dumps which is why almost all of them turn to **** around 75-80psi.

And pretty sure a 450 is not a centrifugal design ? although I havent opened one up

 

Yes the 450 is a centrifugal. I believe the 255 was a gear type pump but I dont remember. But this is the reason the 450 is so much quieter.

 

You can see how they take a fatty at higher pressures. Additionally it shows how voltage changes the current draw (P=V*I) and alos how current demand increases with pressure as well.

I could throw a volt meter and current clamp on the pumps during the tests as well if thats of interest?

 

The 044 is a turbine pump design....maybe the 255 is as well?

 

it doesnt mention there ?

The pumps I've taken apart were either a vane type pump or like a roller cell ( Bosch ). Although a lot of those big Weldon style are obviously gear.

I'd assumed most of the Walbro's were like a vane design

 

Yup a "vane" type is a turbine style pump, but it appears more like a "drum" looking blade assembly.

 

So I have a pretty good writeup I smacked together in about 30 minutes with a bunch of diagrams and whatnot for this upcoming test. Im thinking I should start a new thread as It will be a lot of information and data generated, as well as calculations and some conclusive discussion.

 

can't wait to see the info

 

Unfortunately the more I look at these 044 clones the more disappointing they are. Which is expected for $23 a pump don’t get me wrong. The AEM380 is rated at 90gph at 70psi. Looks like these knock off are lucky to do half that at 70psi. You’d basically need 2 knockoffs to equal 1 AEM380. I’m also not sure they will even reach 100psi pressure wise, which is a bummer.

You would most likely need 4 (or more) of these in parallel to handle big power and they don’t sound like they will be high pressure friendly. At $23 a pop it’s still a very affordable option, but the amp draw is getting pretty out of control with 4+ pumps. I don’t have the spare cash to test 3 AEM 380’s. Price spiked to $150 these too. Picked mine up for $128 shipped last year.

I’m still all for testing the 3 knock offs, but the results won’t be stellar compared to AEM 380’s. Figure 130ish GPH for $70 worth of pump (plus fittings) is still pretty darn good if you ran them all parallel. Assuming the booster pump can handle 100-120 psi like I’m hoping it should be a relevant test anyway.

I’d be willing to throw in 1 AEM380. If anyone else wants to throw in another 1 or 2 we could test those as well I’m sure.

 

I got an AEM pump off Amazon for $112 the other day.

 

Great deal! Wouldn’t mind having a spare at that price. Send it to roastin240 for some quick testing and I’ll send one too. Then we only need one more pump!

 

the aem pump gets the job done. I have one on my nova and replaced a 044 with it. I have ran 9.90 at 137 mph with a single 380. and this year im going to a holley aftermarket reg and running my 380 with a 044 side by side .