Input on electric fuel pump selection

legerwn

Active Member
I'm looking to improve on my fuel system and will start with the fuel pump,

Was looking at the Aeromotive line up but after reading some stuff and input from others that may not be the best selection for the money.

Someone I believe to be knowledgeable in this area has suggested that I look at either a Weldon pump or the Mallory Pro Comp line of pumps.

The Weldon Pumps are out of my price range for now but the Mallory pumps are reasonably priced and have been around for a long time.

I've looked through the posts here but didn't find any info on pump quality or a list of pumps that would be considered top of the line or preferred.

What pump would you suggest for a 700 HP 496BBC (with future upgrades in mind)?

the Mallory pump suggested for my set up was the 5250 Pro Comp pump

thanks Neal
 
Too maintain about 700 horsepower, in theory you need a minimum of about 60- 80 gallons per hour delivered to the engine ,that usually requires about a 140 gph pump flow rate, being needed, too over come the flow losses in the lines, restrictive fittings , etc. that induce flow restriction and turbulence and too over come the inertial loads incurred during transfer and delivery at the 700hp power level, and at least AN #8 or 1/2" inside diam. lines,.... with a return style fuel pressure regulator in the system being strongly advised.
Most failures, I've seen are related to the fuel lines,being too small, the filters being too restrictive or the fittings on the filters or regulators etc being far to small internally to allow unrestricted flow,and of course bad routing that allows the fuel to get over heated ,rather that the fuel pump flow rates,being too low to keep up with demand, provided of course that a semi reasonable pump was selected to begin with, a chart I,ll post below will be helpful.
it makes little sense to buy a fuel pump that pumps lets say 180 gph and hook it to the fuel tank, forced to suck fuel thru a filter rated to flow only 70 gph, yet I see it done frequently!
THINK THINGS THRU,keep in mind you need to avoid doing stupid stuff, REMEMBER THE CONCEPT OF THE WEAKEST LINK IN THE CHAIN, I see frequently like guys who install a fuel filter with fittings that have far smaller and more restrictive internal passages than the lines leading to the pump or a fuel tank with the original 3/8" feed hooked to an adapter to feed AN#8 lines
you never mentioned if this is a fuel system feeding a carb or fuel injection, and as the pressure levels differ that makes a difference in the pump selection
the fact you mention the mallory 5250 that maxs out at 18 psi makes a strong case for carbs!

http://www.summitracing.com/parts/maa-5250,
Id point out that a high quality return style fuel pressure regulator . adequate line size and decent low restriction fuel filters will have a good deal to do with the durability of the pump, as many electric pumps fail due to debris in the lines or not constantly flowing fuel thru the regulator thus allowing the fuel flow to absorb heat in the pump and transfer it away reducing the heat in the electric motor.
the most common issues I see are guys who fail to think thru the flow rates on the fuel filters and the fact that some fittings have considerably more restrictive internal flow characteristics than others,and that fuel pumps push far more efficiently than they "PULL FUEL"

FuelFlowDiagram02a1.jpg

Fuel-Pump-Flow-Requirements.jpg

fuellinesizer.jpg

https://www.summitracing.com/search/brand/ict-billet/department/fittings-hoses
THERES A GOOD DEAL MORE INFO IN THE LINKS

viewtopic.php?f=55&t=211

viewtopic.php?f=55&t=1939

viewtopic.php?f=55&t=635

viewtopic.php?f=55&t=733&p=1030#p1030

viewtopic.php?f=55&t=211&p=275&hilit=fittings#p275

viewtopic.php?f=55&t=6105&p=18854&hilit=fuel+filters#p18854

viewtopic.php?f=55&t=4502&p=21483&hilit=crower+stack#p21483
 
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Thanks for your input Grumpy

I'm running a carb on this one, I missed that in the posting

I've been reading the threads here for a while on the fuel system set up and have plans to upgrade the entire system as outlined here with 1/2" lines and the WIX (AEM) filter suggested in the threads. I still need to visit with the local Hydraulic shop to see what options I have for tubing. I do like the EMT trick with the hose slid into it if I can't get the tubing I need. I've been looking at the Russell Twist-Lok hose and fittings for the lines. The system will be upgraded to the return/bypass style regulator with a dedicated 1/2" line back to the tank.

I want to make sure I get the best pump for the money (size and quality) as I'm starting with the pump and will work through the entire system to bring it up to par as outlined here.

Was curious it you have a certain brand or style of pump that you prefer over others?

Thanks Neal
 
IN a few of the threads here you linked the Edelbrock 1792 pump for reference,

I was looking at this pump for my car but was concerned it may be to close to maxed out for future upgrades and the Mallory pumps were suggested over the 1792 pump.

I'm a firm believer in purchasing USA made and the Edelbrock fits the bill,

I haven't found anything on the Mallory pumps as to if they are USA made,

Neal
 

I can't say for sure about their pumps, but the pressure regulator from Mallory
that I bought is made in the USA. You could always email them and ask, I've done
that before.



 

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as always COST is a huge problem in that, what Id select,in that what I can afford VS what I'd LIKE to select tends to be a bit different, if I was not on a budget what I would use would most likely differ, from what I might settle for, in a few cases, but keep in mind I have been slowly collecting the parts to build my personal big block C4 corvette engine swap for over 11 years now so I'm not willing to compromise on much!
a great many TUNING ISSUES are really fuel delivery issues ,but most people fail to realize that a properly functioning fuel delivery system is critical to making consistent power and manufacturers rarely build much extra capacity into the fuel delivery system in the cars they build over the rated original engines power band, and intended rpm range.
what I'd like to select would be this for that application, a pump with plenty of excess flow capacity , rated at almost the useable pressure

fcd1.jpg

If your current fuel tank or fuel lines can,t keep up with the engines demands, can you remove the current plate and fittings and drill and soldier in a larger dual fuel fittings
fuelplate1.jpg

http://www.tanksinc.com/index.cfm/p...t_id=100/category_id=167/mode=prod/prd100.htm


Tankconnect1.jpg

http://www.jegs.com/c/Fuel-Carbs-Intakes_Fuel-Cells-Fuel-Tanks/10297/10002/-1

http://garage.grumpysperformance.co...es-restrict-fuel-flow-rates.12859/#post-66683

tankfity.png

FuelFlowDiagram02a1.jpg


http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/how-big-a-fuel-pump-do-you-need.1939/

http://garage.grumpysperformance.com/index.php?threads/fuel-pressure-regulators.635/

http://garage.grumpysperformance.co...ss-fuel-pressure-regulators.12776/#post-65958

http://garage.grumpysperformance.com/index.php?threads/input-on-electric-fuel-pump-selection.10664/

http://garage.grumpysperformance.com/index.php?threads/fuel-line-sizing-return-vs-feed.3067/

http://www.summitracing.com/parts/rci-2100ad

http://www.summitracing.com/parts/rci-2172a/overview/

http://fuelsafe.com/store/

http://garage.grumpysperformance.co...ks-and-welding-on-fuel-tanks.6178/#post-61230

http://fuelsafe.com/store/fuel-cells/complete-cells/complete-sportsman-fuel-cells.html

http://www.summitracing.com/parts/rci-2191a/overview/

http://www.summitracing.com/parts/rci-2200ab/overview/
http://www.summitracing.com/parts/qft-30-230/overview/
qft-30-230_sn_xla.jpg

http://www.donaldson.com/en/engine/shoptalk/070451.pdf
http://www.summitracing.com/parts/prm-81794/overview/
http://www.summitracing.com/parts/prm-88864/overview/
prm-88864_w.jpg



no one anywhere can accurately predict exactly what your particular engine combo will find to be the best tune-up specs but any good dyno operation or experienced shop will start with a basic known base line and tweak the combo to get the best results, you'll want a consistent 40 lbs of fuel pressure, you'll want to keep the coolant temps under 200 F
youll want the oil temps in the 200F-210F range
and youll ant the injector pulse duration to stay under 75%-80% at peak rpms , this may require larger injectors, and youll want significantly less than 3 psi of exhaust back pressure at peak rpms.
heres a basic tune

SL1000wAabn.jpg

installing a fuel pressure gauge on your LT1 fuel rail will help provide a slightly higher fuel flow from existing injectors
lt1fl1.jpg

an adjustable fuel pressure regulator allows you the option of feeding the injectors with more pressure which results in a slightly richer fuel/air ratio at any pulse duration.(at times this helps during a tune up)
lt1fl2.jpg


http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/

http://garage.grumpysperformance.com/index.php?threads/how-big-a-fuel-pump-do-you-need.1939/

http://garage.grumpysperformance.com/index.php?threads/diagnoseing-tpi-lt1-problems.1241/

http://garage.grumpysperformance.com/index.php?threads/calculate-fuel-injector-size.1200/

http://garage.grumpysperformance.com/index.php?threads/replacing-a-c-4-fuel-pump.33/

http://garage.grumpysperformance.co...ard-starting-tpi-crossfire-or-lt1-vette.1401/
post your results and more questions
Stoich.gif

EXFLOWZ4.jpg

volumetric.gif
 
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the filters located,between the tank and fuel pump, and the pumps generally located reasonably low inside the frame so it self primes and its protected from impacts, so the filters before the pump,and its fittings are large and not restrictive and the filters easily accessed for frequent replacement and inspection, theres several models, carefully check the thread size on the model you select before you order youll want to find the correct fittings and thread sizes and fuel line sizes ALL before you start spending cash, if the pumps AN#10 thats roughly 5/8" fuel line so that should be roughly the size maintained, you can go from larger to smaller as the fuel travels from the tank to the carb, but try hard to avoid going from small to larger as it always cause flow issues
http://www.summitracing.com/parts/prm-81794/overview/
 
Bigger is better.
Also have to consider a Big Block stump pullung torque on launch & hooks up hard.
The G force on launch can be 1.0 or more.
Literally drives the the pumping fuel back to the gas tank in the rear.
Why front mounted fuel cells popular again on 2,000-3,000 Hp super street cars in 7's && 6's.
 
with the perma-cool filter/seperator do I still need a filter at the the carb?

On the Perma-Cool web site it says fitters down to 2 microns and flows 5 GPM (300 GPH if my math is right).

Seems that should take care of the fuel system filtering requirements.

Two different filters are linked, one with 3/4" inlets/outlets and one with dual 1/2" inlets/outlets,

I like the idea of feeding the filter with dual -8 inlets, the sump I'm looking at has two -8 AN fittings. I can use both to feed the filter and pump.

The pump is back ordered so it will be November before I can get it (Mallory 5250).

Would love to see how others have plumbed their fuel system if yawl have any pics?

Thanks Neal
 
legerwn said:
with the perma-cool filter/seperator do I still need a filter at the the carb?

On the Perma-Cool web site it says fitters down to 2 microns and flows 5 GPM (300 GPH if my math is right).


Would love to see how others have plumbed their fuel system if yawl have any pics?

Thanks Neal
Two microns is really getting down there, most filters for performance automotive are 10 microns and usually go after the pump. If you look at the bottom left example below, that's 25 micron. Notice at 100 microns you can no longer see the yellow background thru the mesh.



You might browse this thread for some ideas. I have not actually done the install yet, that's a project for this winter.

viewtopic.php?f=55&t=7787

 

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You can get away with a great deal more on a lower power car than you can on something that has a real need for accurate fuel delivery, a 400hp-450 hp car can get by with 3/8" or an#6 fuel lines and almost any fuel pump that supplies 70gph-90gph,at 6-7 psi and youll hardly notice any difference if the fuel pressure varies a few PSI, from lets say 4psi-6psi at the carb inlet port, youll hardly notice. but if your running at 600hp-800hp, or more ,power levels, things are far different, and your engines, dependent on a consistent fuel air mix and dependable ignition advance. tune becomes far more critical, random, changes in fuel delivery volume and pressure changes can mean broken parts in very short time frames. in theory the carb might benefit from a second fuel filter in the line between the pump and carb inlet port too catch crap if the fuel pump self destructs, and there are certainly decent full flow filters available, like this one
http://www.summitracing.com/parts/WIX-24003/
WIX-24003.jpg

but your main source of crud is from the fuel tank and contaminants in the fuel you buy, that your constantly pouring into that tank,from Lord only knows what sources, at times.
but Ive yet to see these brass inlet filters that need to be replaced occasionally not do that job as long as they are replaced occasionally, if you install a high quality high flow filter between the tank and fuel pump,youll tend to prevent much of the pump wear issues that not having a decent high flow low restriction filter located before the fuel reaches the pump, can cause, thus having the pre-filter avoids
filterBF.jpg

filterCF.jpg

filterDF.jpg

filterEF.jpg

filterFF.jpg

filterGF.jpg

filterHF.jpg

555-15901_flow.jpg

As I'm sure your aware most pumps fuel flow rates are rated at ZERO back pressure flow rates unless specifically listed other wise thus a 140 gph fuel pump rating may and most likely does flow around 70-80 GPH (MUCH LOWER) when you run it up to a carburetor and fuel pressure regulator set at 6 PSI
FuelFlowDiagram02a1.jpg

Fuel-Pump-Flow-Requirements.jpg

fuellinesizer.jpg


THERES A GOOD DEAL MORE INFO IN THE LINKS

viewtopic.php?f=55&t=211

viewtopic.php?f=55&t=1939

viewtopic.php?f=55&t=635

viewtopic.php?f=55&t=733&p=1030#p1030

viewtopic.php?f=55&t=211&p=275&hilit=fittings#p275

viewtopic.php?f=55&t=6105&p=18854&hilit=fuel+filters#p18854

viewtopic.php?f=55&t=4502&p=21483&hilit=crower+stack#p21483
 
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Grumpy,

Most manufactures recommend a 100 micron before the pump and 10 micron after the pump. Just want to make sure ..... you don't think that 10 micron or less filter before the pump is NOT too restrictive for an electric pump???

 
I,m not too concerned with the micron count on the filter even 100 micron count filter element would catch 99% of the crud that might damage a fuel system, if it had a 100 micron count it would be fine, it has a 2 micron, but that does not restrict flow, because like an oil filter it has a huge surface area, and fuel is very low viscosity, fluid.
the point here in my opinion is mostly to have a high flow capacity filter thats easily accessed and fairly cheap and easy to change so its changed occasionally as doing that is critical to maintaining the durability of the fuel pump and the whole fuel system, the main advantage of using a fuel filter like this is its large internal filter surface area that allows it to have almost no measurable flow restriction and the ability to spin that valve on the base to check/test , drain off a bit of the fuel for a regular test for water contamination in the fuel supply,today,s E10 pump fuel tends to contain , or readily collect water from air moisture and water quickly kills the internal parts in fuel pumps,the basic filter , DESIGN, that traps and blocks water from reaching the fuel pump,which is a major reason electric fuel pumps fail, and the ability to spin off the filter like a common oil filter, with an easily carried and easily replaced spare, and quickly replace it if you find its got trapped crud in the filter.
READ THIS
http://autolabscopediagnostics.com/fuelpump.htm
prm-81794.jpg

watersep.png

fuelsepa.png
 
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I like that fuel water seperator best Rick.
Theory is sound with todays E10 gas.
 
appriciate all the input,

I've settled on the pump and now am looking at the upgrades to the lines,

My plans for the engine in the future are to pull it and add another 1/4" stroke to bring the engine to a 540 ci. and to shot for the 800 HP range.

I'm planing to bring the fuel lines to -10 (5/8") both supply and return, this should be adequate for the HP.

I'm going to sump the tank with dual -8 fittings for the supply to the perma-cool water/fuel separator as posted previously in this thread with two 1/2" inlets and outlets.

The regulator will be the recommended 4300M Mallory return style plumbed to a -10 line back to the tank as Mallory indicates this regulator will flow the needed 250 gph that the pump puts up.

I've still got to visit the local hydraulic shop to see what my options are for the hard fuel line. I don't think it will be an issue as they have been very helpful in the past when I needed help with fittings and hoses for this build that were out of the ordinary.

Appreciate any input,

Indy I looked over your thread and have to say that your build is very impressive and well thought out, thanks for sharing

Neal
 
I ordered the Mallory 5250 Pump and the Mallory 4300M regulator, also ordered 2 -3/4" SS mini ball valves for the sump (.49" bore).






fitr1.jpg

fitr2.jpg

fitr3.jpg

The pump was hard to get without waiting till November as they are on back order just about everywhere. I stumbled across Pep Boy's web site where the pump was heavily discounted and was able to add the 25% discount along with free shipping on top of the discounted pump and they have the pump on hand so it shipped right away.

I'll be using both 8AN sump fittings to feed the fuel/water separator so I needed two valves.

Grumpy, looking at a post on the form there is pic of the rear of a vette with an Aeromotive A1000 pump plumbed from the tank to the pump. Not sure if you were doing the work on this car or not but am needing ideas on how to get the supply line form the rear of the car past the half shafts to the frame rail. The OEM line passes over the top of the frame near the tire and I don't think I'll have room to get two 5/8" lines in that area. I've seen pics were the lines were run below the diff with a shield, I don't get a good fuzzy feeling about running them there.

any ideas on how to get the lines from the rear of the car to the frame rails ahead of the half shafts?

Neal
 
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The best way would to be use a fuel cell Neal.
15-30 gallons. Or fabricate a fuel cell from scratch.
Not the easiest for the home mechanic to do without prior experience .
 
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