100+ PSI fuel pressure

Pizza pig · Jun 3, 2012

I should have my truck running this week, and this really has me curious to see what my pressures are with 90s on all 4 ports. I took my a1000 off because It started making weird noises and fuel pressure was dropping. Pulled my filters and they were dirty so I thought the restriction killed the pump.

BUT, when I went to remove the a1000 and install the fuelab, i noticed the ground on the pump was a little loose... BINGO, at least I think so. Im going to send it off to aeromotive and have them test it and go through it to see if it needs anything. If it comes back ill keep it in my tool box as a spare just in case, never hurts to have a spare.

I mainly went fuelab for the fact they use brushless motors. That and they have the ability to be set at reduced speed for continuous duty (a1000 is not, unless its the eliminator pump or marine). The equivalent from aeromotive was far more expensive, and the fuelab offers cool colors, now my green pump matches my green regulator LOL Gotta have flair :rockon:

Twan · Jun 3, 2012

I see what your saying, but the pump will push it's max psi until it hits the regulator, I bet if you put a gauge on before the heads, and after the heads, not on the regulator it will show within 5 psi. On the airamotive sight, they say to run a filter, pump, filter then the regulator, then to the carb, the return is on the regulator. So in your case, you need a regulator before and after the heads. To keep pressure in the heads.
Atleast this is my thoughts.

IdahoF350 · Jun 3, 2012

Twan, the carbureted setup you are referring to would be just like the factory stock system, with the regulator before the head, then dead heading into the heads. On a race car with a big carburetor and a huge fuel need, but where that need is short term, a few minutes at most, it's not an issue. But on our trucks, one of the more compelling reasons to go the full flow route from the front to back of the heads is to use the fuel as a means to cool the injectors.

Honestly, the A1000 is more pump than is needed, and that would be evidenced by the 100psi WOT pressures mentioned previously. The A1000 was designed to move enough fuel to support 1000hp on a naturally aspirated gasoline engine, roughly 800hp on a forced induction engine due to the higher operating pressure to offset the fuel pressure delta into a pressurized intake charge. We're not using it for that purpose here. And we're not flowing gasoline, but rather diesel. I would have to crunch some numbers to get exact, but this pump will flow way more than 1000hp worth of diesel fuel even in the 55psi range.

I'm shocked that there isn't an "drop in" replacement for the stock pump on these trucks that supports the fuel flow required by 90% or more of the modified trucks out there. Surely a few small tweaks to the stock fuel system and these trucks could support 205s or maybe even 225s with relative ease. And yes, I've had my truck apart and seen how small the lines and everything are, but knowing that the stock system can support nearly 500whp these days, what's the hold up. The stock lines to the heads look to be about a 4mm I.D. so a 6mm or 8mm I.D. would be a massive upgrade in terms of volume. To my mind, -4AN Teflon lines would be a solid improvement, -6AN Teflon would be HUGE!

I'm thinking about all this stuff and seeing what everyone else is doing right now to get data for my own truck. I don't want problems, but I want more power. I know I'll need a little more than stock fuel delivery for the 155/40s I have planned, but I'm not about to go crazy here. I'm in Commiefornia so it has to "look" stock to pass the visual portion of our retarded emissions inspection process. I can always de-fuel the tune to pass the snap test for smoke.

Agjake11 · Jun 3, 2012

pizza pig said:
I should have my truck running this week, and this really has me curious to see what my pressures are with 90s on all 4 ports. I took my a1000 off because It started making weird noises and fuel pressure was dropping. Pulled my filters and they were dirty so I thought the restriction killed the pump.

BUT, when I went to remove the a1000 and install the fuelab, i noticed the ground on the pump was a little loose... BINGO, at least I think so. Im going to send it off to aeromotive and have them test it and go through it to see if it needs anything. If it comes back ill keep it in my tool box as a spare just in case, never hurts to have a spare.

I mainly went fuelab for the fact they use brushless motors. That and they have the ability to be set at reduced speed for continuous duty (a1000 is not, unless its the eliminator pump or marine). The equivalent from aeromotive was far more expensive, and the fuelab offers cool colors, now my green pump matches my green regulator LOL Gotta have flair :rockon:

how long were the filters on there?

Pizza pig · Jun 3, 2012

8k miles I believe, I also found plastic in the filter from when I did the non tank drop sump. This is why I NEVER recommend installing a sump without the tank out of the truck. I was meticulous cleaning the tank with a shop-vac and stuck my hand in there to get everything, and still I found plastic in the filter. When I replaced the tank I did it off the truck and Im much happier with the results and I brake cleaned the entire inside of the tank making it spotless.

Ill keep you posted when I send the pump back to aeromotive and hear what they have to say.

Agjake11 · Jun 3, 2012

i was wondering what the interval might need to be on these filters. i should be up and running tomorrow and i now wish i had gotten the fuel press adapter fitting that i saw online so i could check these things other places then off the regulator

Joshbaker · Jun 4, 2012

This is all interesting. (and over my head) So I have a few questions that may sound dumb. If you have 100 psi in one place and 55psi at the regulator. Which one is the pressure at the injectors? And I thought 70psi was the most you should go on a 6.0L???

Twan · Jun 4, 2012

Give or take a few psi, 90-100psi. The pump will push it's max till it hits the regulator. I would like to see some people test there setups, a regulator can't control the pump pressure, it controls what it let's by.

FX4 F2-Fifty · Jun 4, 2012

Joshbaker said:
This is all interesting. (and over my head) So I have a few questions that may sound dumb. If you have 100 psi in one place and 55psi at the regulator. Which one is the pressure at the injectors? And I thought 70psi was the most you should go on a 6.0L???

Honestly i have no idea, but that is why i posted this thread. If the restriction is before the heads, then probably around 55psi, if the restriction is at the back of the heads then probably 100psi at the injectors. Not a dumb question at all. When i hooked up the gauge i thought it was broken, so i pulled out a mechanical gauge to double check. I want to have 55-60psi before and after the heads if that is possible.

Twan said:
Give or take a few psi, 90-100psi. The pump will push it's max till it hits the regulator. I would like to see some people test there setups, a regulator can't control the pump pressure, it controls what it let's by.

So i have a spare a1000, and i hook it up with 5/8 line on both ends of the a1000 and turn it on. Your saying that with no restriction that the pump is instantly going to put out 100psi? No, it will flow high volume at a low pressure. Now if i take my finger and partially close the end of the hose(regulator), the pressure will rise in the hose depending on how much restriction i create.

Yes the pump will push its max all the time, but i want that max to be the volume at 55psi. These pumps are NOT designed to pump at 100psi.

A1000 flow chart.
http://aeromotiveinc.com/wp-content/uploads/wpsc/product_images/11101-chart.jpg

Edit: here is what were working with EFI and here is a carb setup.

Twan · Jun 4, 2012

The pump I was looking at was a 100 psi pump.
Please try this, don't change anything, check your fuel presure after the heads, right before the regulator, not on the regulator, I bet you will still have 90-100 psi. I see what your saying.
Feel free to call might help us understand each other better.
970-744-0781.

09stroker · Jun 4, 2012

If the entire system is properly sized for the pump flow, the pressure should be what the regulator is set at (post pump)

09stroker · Jun 4, 2012

Twan said:
The pump I was looking at was a 100 psi pump.
Please try this, don't change anything, check your fuel presure after the heads, right before the regulator, not on the regulator, I bet you will still have 90-100 psi. I see what your saying.
Feel free to call might help us understand each other better.
970-744-0781.

Explain how that would be If the gauge port is Measuring the inlet pressure. This isn't like a compressed air system, they are bypass regulators.

Twan · Jun 4, 2012

Someone test it and see. Check pressure at the pump then before there regulator, I know what your saying, but your not seeing my point.
Or call tonight, I might be misunderstanding you.

alwil · Jun 4, 2012

I have never seen a regulator that regulates upstream pressures.....I would bet that you have 100psi at the regulator also.

2wd-fire · Jun 4, 2012

pizza pig said:
I just took my a1000 off, but I can try and get a pressure reading from my fuelab pre regulator.

What fuel lab you get 42401?

Pizza pig · Jun 4, 2012

fuelab 41401

SICKS LITER · Jun 4, 2012

FX4 F2-Fifty said:
Honestly i have no idea, but that is why i posted this thread. If the restriction is before the heads, then probably around 55psi, if the restriction is at the back of the heads then probably 100psi at the injectors. Not a dumb question at all. When i hooked up the gauge i thought it was broken, so i pulled out a mechanical gauge to double check. I want to have 55-60psi before and after the heads if that is possible.

what size are your fuel lines from the tank to the pump, from the pump to the engine, to each cylinder head and out the back to the regulator? what size is your return line out of the regulator?

SICKS LITER · Jun 4, 2012

if youre using the stock return line that is not helping the situation.

FX4 F2-Fifty · Jun 4, 2012

Twan said:
The pump I was looking at was a 100 psi pump.
Please try this, don't change anything, check your fuel presure after the heads, right before the regulator, not on the regulator, I bet you will still have 90-100 psi. I see what your saying.
Feel free to call might help us understand each other better.
970-744-0781.

I dont have anyway to measure it right before the regulator. But as it was said the gauge port is on the inlet. before it hits the diaphragm so it will be the same?

09stroker said:
If the entire system is properly sized for the pump flow, the pressure should be what the regulator is set at (post pump)

:whs: this is what i would like to accomplish.

alwil said:
I have never seen a regulator that regulates upstream pressures.....I would bet that you have 100psi at the regulator also.

verified with two gauges that i only have 55psi at the regulator.

SICKS LITER said:
what size are your fuel lines from the tank to the pump, from the pump to the engine, to each cylinder head and out the back to the regulator? what size is your return line out of the regulator?

5/8 from tank to pump. 1/2 from pump to fuel block. Not sure what size the AN lines are going to the heads. and out the back of the heads it is stock banjos and hardlines up over the rear of the motor and then the same size AN from the hardlines to the regulator. Its an Elite fuel system that was designed to use the stock fuel bowl originally.