a1000 pump questions?? doesnt add up

ok im confused, aeromotive claims 600 lbs/hr of fuel from their a1000 pump, and 800hp with FI, but a walbro 255 can do only 404 lbs/hr and can also do 800hp?? whats up with that? i cant decide on twin intank 255's which would be 808 lbs/hr ...or the a1000, which by their claims of only 800 hp, wouldnt be enough, but 600 lbs/hr is alot of fuel!! can someone clear this up for me?

im just trying to decide on a fuel system for a twin t-70 355 lt1, 8.4 CR ...looking for 1000rwhp on race gas

We promise 600 #/hr @ 45 psi. This is the minimum volume expected from a shipping pump @ 13.5 volts. That is good for 1100+ horsepower naturally aspirated @ around .55 bsfc. The reason we rate the forced induction horsepower lower is two fold: One you can expect the pressure to be higher in the fuel system under boost, which lowers the flow of any pump. Two if a blower is used your bsfc will be higher because of the parasitic drag of the compressor. It may take 50+ horsepower to drive the blower that you lose from the flywheel. So your fuel requirements are higher than measured horsepower.

I do not have a flow sheet from a Walbro 255lph pump and I do not know if the flow rating is at pressure or free flow. Maybe one of the supporting vendors such as Racetronix can provide that information to you. It is not on the Walbro public site.
We will probably pick up a pump to test at some time and map out the flow. I will try to provide that information to the forum when it is available.

From what I have found on the net the rating is @ 43.5 psi. In which case the dual intank setup would be enough for well over 1000 hp assuming the rest of the fuel system was up to the task.

I do not have a flow sheet from a Walbro 255lph pump and I do not know if the flow rating is at pressure or free flow. Maybe one of the supporting vendors such as Racetronix can provide that information to you. It is not on the Walbro public site.
We will probably pick up a pump to test at some time and map out the flow. I will try to provide that information to the forum when it is available.

From what I have found on the net the rating is @ 43.5 psi. In which case the dual intank setup would be enough for well over 1000 hp assuming the rest of the fuel system was up to the task.

All Walbro specs are at 43.5PSI @ 13.5V unless the application is specific to a 58PSI / 4 bar system in which case it would be apx. 220L/Hr. Stoddard solvent is used. A DP will support in excess of 1000HP in theory but most people want to run them with factory lines, rails and filters which drops that number considerably. There are many published charts that can be found on the internet listing Walbro's specs.

Here is a chart showing the spec @ 12.0 volts http://www.racetronix.com/images/Fuel_Pumps/340vs307_graph.jpg
Here are a few charts comparing the various in-tank pumps on the market: http://www.stealth316.com/2-fuelpumpguide.htm
Here are some other flow charts for their in-line pumps: http://www.gnttype.org/techarea/fuelsystem/walbroflow.html

Hope this helps.

Jack :cool:
Racetronix

yes, that actually helps alot, thanks. ive got the lines and rails set up just about as good as possible...haha...so depending on price, im leaning toward the dual setup, thanks for all your help, racetronix and mark

These threads are good too:

http://forums.corvetteforum.com/showthread.php?t=1008469&forum_id=87

http://forums.corvetteforum.com/showthread.php?t=1029195&forum_id=87

I used to be a fan of the aeromotive pumps, but I have found that a pair of walbros offers the needed flow, similar cost, but MUCH quieter, and seemingly more reliable.

ok im confused, aeromotive claims 600 lbs/hr of fuel from their a1000 pump, and 800hp with FI, but a walbro 255 can do only 404 lbs/hr and can also do 800hp?? whats up with that? i cant decide on twin intank 255's which would be 808 lbs/hr ...or the a1000, which by their claims of only 800 hp, wouldnt be enough, but 600 lbs/hr is alot of fuel!! can someone clear this up for me?

im just trying to decide on a fuel system for a twin t-70 355 lt1, 8.4 CR ...looking for 1000rwhp on race gas

I can't tell you any specifics other than I was running out of fuel at 650 RWHP and the A1000. Moving up to 2 of them now.

--Sean

In all fairness to Aeromotive, many people who install their pumps do not realize that they must be gravity fed with a properly sized non-collapsing suction line but instead end up mounting them way above tank level using undersized rubber hose. To install a gravity feed system in a street driven car can be somewhat tricky as most factory fuel tanks are pretty low in the vehicle as it is.

There is a wide variation in pump gasoline composition. Depending on where you are located, certain types of solvents (Xylene, Toluene, MTBE, Ethanol etc.) in pump gas attack the adhesive used in the assembly of Aeromotive pumps. markinkc69z can correct me if I am wrong but supposedly Aeromotive has a special-order fix for this?

The Walbro pump's design stems from the OEM market offering the following advantages:

They are very quiet when compared to most other external in-line pumps.
They need not be gravity fed
They exhibit exceptional MTBF ratings
They have low current demand
They are small in size
They can be run in parallel independently thanks to an integral checkvalve
They are tolerant of most solvents and alcohols in today's pump gas
They are very affordable with an average internet / street price of $130-$160 each

Walbro and Aeromotive pumps both perform well when properly installed and each has its own benefits over the other depending on the application.

Jack :cool:
Racetronix

We addressed the magnet delamination issue some time ago by a redesign of the magnet retention in the flux ring. This applies to all shipping pumps.
We test the A1000 and rate it at 2500+ hours lifespan at efi pressure. There is almost always a pump running for durablity testing here.
Our pumps make exceptional vacuum compared to a typical performance fuel pump. This vacuum can cause cavitation if the inlet is restricted. It also allows for a bit more mounting latitude if need be as long as all of the inlet plumbing is as recommended. Our pumps can be tank mounted as well, and there is a gentleman that has built his business off of this.
As Racetronix says, each of our approaches has its application. At Aeromotive we do not try to be all things to all people. Our product mix appeals to much of the market, but is not appropriate in some instances. If you were to call and ask we would tell you if we thought there was a better solution to a specific application and try to tell you where to aquire it. I'm glad to see that we are building a bit of harmony.

So you're saying you can mount some of your pumps in tank as well, or not sumped anyways? Have a 82 Vette making 400-450 hp at the engine as well as a 150 wet shot of nitrous. It's running a carb, so it doesn't need high pressure. Got an electric pump we can use on this without sumping the tank? Who is this gentleman you're referring to, and do you have any pics of these installs? Thanks.

http://www.rickshotrodshop.com/

He offers a selection of stainless steel replacement tanks that incorporate our A1000 pump.
Our 11203 pump is suitable for over 900 hp carbureted. Its bypass is set @ 19-20 psi. Its a t-style vane pump designed for continuous use. 3/8" pipe fittings.

So would the A1000 be able to support more horsepower on a turbo motor since there is no drag from a blower belt?

I've been leaning towards two external GSL392 pumps on my S10, but if I can use a single pump to meet my goals then I'm all for it.

So would the A1000 be able to support more horsepower on a turbo motor since there is no drag from a blower belt?

I've been leaning towards two external GSL392 pumps on my S10, but if I can use a single pump to meet my goals then I'm all for it.

Just as a note, a single GSL392 will support upwards of 600RWHP+ @ 43.5PSI given the proper plumbing and wiring system. You need to be making some serious HP to justify two GSL392 pumps.

The plans are either a 383 or larger small block with Dart 215 heads, and a pair of PT-61 turbos. 15 PSI on the street and autocross (maybe less). Probably low 20's at the track. Just have to finish my TA project before I can continue with the S10. I've got everything pretty much mocked up, all I need right now is a rotating assembly for it. I'll pick one when I decide on how many CID I want to run.

A single A1000 will supply enough fuel @ 60 psi for at least 800 hp. You need to figure your fuel volume requirements at your base pressure + boost. With base pressure being 43.5 stock and your boost being 15+ figure your requirements at 60psi. The A1000 will flow over 400# /hr there @ 12 v. Over 500# @ 13.5 which is what the pump is likely to see on a street car with an alternator.

hey mark, i am putting together a system for a turbo motor, i'm looking for 700-800hp out of it running a single t76gts.
i'm wrapping up the fuel system now, can you tell me what kind of pressure to run? i sumped the tank by welding bulkheads into the bottom, a -10 for the feed and -6 for the return.
i run -10 to the prefilter, then the pump and then -10 all the way to the front to the second filter. i'm using a 3/8 4 port aeromotive regulator, one comes from the filter into the reg and two split out to each fuel rail which has -8an fittings and matching line. then a -6 goes back to the tank.

i haven't decided on an injector size yet, i expect to run around 20#'s of boost to acheive my goal. i am using an a1000 pump and all areomotive filters and regulator. aeroquip fittings and braided lines.

is the -10 braided line correct for that pump then?! i know to mount it low, can it be at mid tank level or does it need to be below the tank?

so how should i rate my injectors and what kind of pressures will the a1000 handle?

thanks,
mike

A 72 lb LowZ injector would deffinitely handle the fuel delivery requirememts, but requires a peak and hold driver circuit such as the accel variable injector controller for an OE ecu. You would probably want to upgrade to an aftermarket controller though for a boosted application so you can adjust fuel delivery vs. boost. Your fuel pressure will be dependant on what injector you go with, the amount of control your ecu provides and the airflow capacity of the engine after it all comes together. I don't have a magic formula for you to determine fuel pressure ahead of time. The A1000 as noted will supply over 500 # hr @ 60 psi and 13.5 volts. That is enough fuel for 900 hp at a BCFC of .55 . It will supply over 450# at 70 psi. Enough for over 800 hp. The 72 lb injector is good for about 900 hp at its rated 43.5 psi at an 85% duty cycle.
The 72lb injector may give you a fat idle though Without going to 16 staged injectors, its a price you may have to pay.
The regulator is boost referenced so it maintains a constant pressure differential across the injector. So even though manifold and fuel pressure is rising, injector flow rate will remain relatively unchanged. The fuel delivery of any fuel pump will decrease with pressure, so it is important to know what the ultimate fuel pressure will be (under boost) to determine if enough volume is available.
Injector pressure flow rate change formula:

newFlow= (sqrt(newPress/oldPress))*oldFlow