Eddy mechanical fuel pump

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gm1236

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How good does the eddy mechanical fuel pump #1723 with the 3/8 npt fittings work? Currently have a Carter 1/4 npt fittings with 3/8 line that can’t keep up. Plan on running a #8 line from a tank with a sump to a 750 Holley on a 383.
 
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What's the part number on the Eddie?
That will tell you fuel pressure and flow

Then see if your 383 needs more or not
 
according to the interwebs, that pump is good for up to 600 HP
even with a 3/8 line that pump should do just fine

are you sure the engine is outrunning the fuel pump and not some other part of the delivery system?

(ive had the flexible line between the pick up and the hard line collapse before, cutting of fuel to the engine, just to mention something)
 
Trust me...it can be screwed up. You'd think not, but there is probably a way to do it, and someone can find it.

unless you put the arm on top of the eccentric, or rotate it so that the outlets face into the block...I guess there are a few options
 
Thanks for the replies. I’m updating the fuel system and I was hoping somebody has some experience with this pump. I can accomplish what I want with an electric pump and regulator, but the car is mostly street driven. I’d prefer the mechanical pump so I don’t have to listen to the electric one.
The car currently has the good carter pump and 3/8” aluminum line, which is only 1/4” I’d, along with some kinks and tight bends. It all needs to go. Fuel pressure will drop to 1-2lbs when I get on it. The car has gone mid 12’s running out of fuel in full street trim. It’s got some nuts, can’t wait to see how it goes with enough fuel.
 
Do a volume test;
The scuttlebutt is the engine needs a half a pound per horsepower per hour. Therefore,
at 400hp, the requirement is; 200pounds per hour, is 33.33 gallons per hour, is .5555 gallon per minute, is 71 ounces per minute ........ is 17.78 ounces in 15 seconds....at full load full rpm.
>Your #1723 rated at 110gpg, and the volume test will tell the tale. The catalog says that pump is good to 550 hp, which maths out exactly to 1/2 pound per hp per hour.The 110rating would provide 58.7oz in 15 seconds, but I know not at what rpm. And this spec is about triple what a 400 hp engine needs.
>The engine don't care about fuel pressure. The carb either. It only cares that the bowls are filled to the design level, and stay there. When the pump is running at max capacity, free-flo, it will be at zero psi. The pressure when reading high, only tells you how LITTLE fuel may actually be flowing, because the pressure rises to the max when the floats shut off the leak. Some guys say the pressure should be 3.5 to 4 at WOT and charging, to overcome inertia in the line and guarantee fuel is actually flowing. IDK about that cuz I have no gauge. I find that gauges just cause my worry. The only gauge I keep an eye on is the Speed-O-meter.......oh, and the fuel-level gauge, cuz I'm not a fan of walking.
>The engine-mounted pump is a suction pump, and every bend and kink is a volume killer, and so is a 12 foot column of fuel in a half-inch line, when charging to the traps.. But the biggest restriction of all, is inside the sender if it is still the 5/16, with a miserably varnished up sock on the end. Or if the tank venting system has failed.Well; a loop of rubber hose from pump to supply line might become the biggest,lol, if it gets sucked flat.
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For reference;
My car has a 3/8 supply line from right into the 87E10 gasoline, to a Mopar P4007040 mechanical pump (rated at 80gph), into a Holley 750DP. I ran my supply line right to the pump, put a bubble-flare on it, and jumpered over it with EFI hose. I left the hard line some room for engine movement, but strapped the engine down fairly tight.
This car ran 93mph in the Eighth on that; @3457 pounds, @930 ft., which the Wallace calculator estimates is 433 hp, and predicts 115 in the quarter. She's running a 10.5PV, and I think 72/80 jets.
I used; 1 gUS is 128oz; is about 6 pounds.
 
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Do a volume test;
The scuttlebutt is the engine needs a half a pound per horsepower per hour. Therefore,
at 400hp, the requirement is; 200pounds per hour, is 33.33 gallons per hour, is .5555 gallon per minute, is 71 ounces per minute ........ is 17.78 ounces in 15 seconds....at full load full rpm.
>Your #1723 rated at 110gpg, and the volume test will tell the tale. The catalog says that pump is good to 550 hp, which maths out exactly to 1/2 pound per hp per hour.The 110rating would provide 58.7oz in 15 seconds, but I know not at what rpm. And this spec is about triple what a 400 hp engine needs.
>The engine don't care about fuel pressure. The carb either. It only cares that the bowls are filled to the design level, and stay there. When the pump is running at max capacity, free-flo, it will be at zero psi. The pressure when reading high, only tells you how LITTLE fuel may actually be flowing, because the pressure rises to the max when the floats shut off the leak. Some guys say the pressure should be 3.5 to 4 at WOT and charging, to overcome inertia in the line and guarantee fuel is actually flowing. IDK about that cuz I have no gauge. I find that gauges just cause my worry. The only gauge I keep an eye on is the Speed-O-meter.......oh, and the fuel-level gauge, cuz I'm not a fan of walking.
>The engine-mounted pump is a suction pump, and every bend and kink is a volume killer, and so is a 12 foot column of fuel in a half-inch line, when charging to the traps.. But the biggest restriction of all, is inside the sender if it is still the 5/16, with a miserably varnished up sock on the end. Or if the tank venting system has failed.Well; a loop of rubber hose from pump to supply line might become the biggest,lol, if it gets sucked flat.
xxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxx
For reference;
My car has a 3/8 supply line from right into the 87E10 gasoline, to a Mopar P4007040 mechanical pump (rated at 80gph), into a Holley 750DP. I ran my supply line right to the pump, put a bubble-flare on it, and jumpered over it with EFI hose. I left the hard line some room for engine movement, but strapped the engine down fairly tight.
This car ran 93mph in the Eighth on that; @3457 pounds, @930 ft., which the Wallace calculator estimates is 433 hp, and predicts 115 in the quarter. She's running a 10.5PV, and I think 72/80 jets.
I used; 1 gUS is 128oz; is about 6 pounds.
Thanks AJ that’s is some very interesting information. I guess a volume test is the first thing to do, to get a baseline of where the fuel flow is at now. How can this be done effectively and safely with a mechanical pump? Disconnect the line, put in a jug and crank it for 10 sec?
 
The fully warmed up and properly operating engine, will idle a long time on whatever fuel is in the bowls; perhaps 1.5 minutes or more.
For a preliminary test I stick a tiny funnel into the vent stack, and keep a 500ml bottle of 4% mixed 2-cycle gas nearby. Then redirect the pump output into a clear 2-liter pop bottle, with a clear hose, that I put on the bottom of the bottle, and then I start her up. This is a preliminary so I'm not real interested in quantity yet, so much as color and freedom from water and bubbles.
If it ain't clear I fix that. And if it has air bubbles or water in it, then I go fix that first.And if the engine idle speed changes, I dribble some gas into the float-bowl, thru that vent, before it stalls. But the hose stays submerged in the bottom of the bottle at all times.
If you had a lot of fixing to do, it now may be that the pump is filling up your pop-bottle likidy split, so perhaps the volume test can be skipped.
If there was nothing to fix, Well then, you have to do the test.
The FSM test is done at something like 500 rpm, but good luck with that.
Fill the bowl and make level mark on the bottle, then start her up and run her for 60 seconds noting the rpm, then shut her off, and measure the quantity of fuel down to the mark you made. If the engine runs outta gas before the minute is up , make a note of the time it ran.This test does not have to be dead nuts accurate because the pump is rated at near triple what a 400hp engine needs.
Then you can extrapolate your finding to whatever rpm you want, and probably be close enough.
Worst case; the engine stalled at 39 seconds and pumped whatever measure of fuel . You need to convert that to a 15 second spec so this would be 39/60 , times the amount pumped, then divided by 4; right? Ok then moving on;
Say she was idling at 800rpm and your engine revs to 5600 Then 5600/800=7 to 1, and so your output needs to be about 1/7, of the formerly estimated ~18 oz in 15 seconds. If you get double or more than that, then there's no point in trying to be any more accurate , yur done.
But if your pump is skimming the requirement, or worse, then it's getting serious.
I'm a lil muddy in the head today, so if this seems muddy to you, then just PM me or perhaps someone else will jump in with clearer words.
 
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Thanks AJ. I was thinking of doing just what you explained, let it idle until it shuts down. I like your formula for figuring flow at high rpm. Makes perfect sense to me. I’ll give it a try one of these days.
 
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