Fuel flow

Kdw1403 · 05-07-2017, 07:18 PM

how much fuel should a fuel pump for a fuel injected motor free flow per minute? can i take mine fuel line off at the fuel rail and turn on pump and measure how much fuel it pumps in a minute. Actually i only do it for 20 seconds and times that X 3.. old time way. May not work with fuel injection. Is my math correct that if a aeromotive A1000 pump flows 600lbs per hour would that be 96.77 gallons per hour (gph)? If my math is correct wouldn't that be a little less than the old holley blue pump?

Buick6 · 05-07-2017, 08:19 PM

In all honesty, if I were you I'd call the Aeromotive tech line and discuss your fuel delivery problems and get some recommendations from them.

https://www.aeromotiveinc.com/tech-help/

Rich Biebel · 05-07-2017, 08:30 PM

It's pretty dangerous trying to flow test a high pressure pump to me like that. I had an LT-1 EFI powered car and it had an Aeromotive A-1000 pump. It had a Paxton pump previously that failed the first time I raced the car. I replaced it with and The Aeromotive was exactly the same. With 24lb injectors I ran some 10.50's in good air back in 2006. The same car has run 10.20's and probably still has the same pump and fuel system. I ran 50lbs pressure and experimented with higher pressure once....It slowed down. I have an all Aeromotive fuel system in my dragster and their stuff is excellent. The design of that pump has magnets epoxied to the outer housing. It has brushes and an armature. If your reading very low pressure and voltage running the pump I would pull the pump out and I would take it apart and inspect it or bench test it. You could power it and pump a fluid less volatile than gas.....mineral spirits.....

Ed Wright · 05-08-2017, 09:45 AM

Rich, raising the fuel pressure makes your air/fuel richer, if you don't lean it back down in the ECU. I found six hp, in A-B-A testing on the dyno raising my fuel pressure from 45 to 60 psi, with the air/fuel tuned back to the same values with both fuel pressures. (Be certain to enter your new injector flow rate with the new fuel pressure) Nothing else changed in the ECU. After tuning the A/F ratio back to the numbers that made the best power at 45 psi. To verify it wasn't something else did it, I put the 45 psi tune back in the ECU, made another pull, lost my new 6hp. Turned it back up to 60, put the 60psi tune back in it, got my new 6 hp back. Same 13.1-1A/F both ways.
Your results may vary.

Rich Biebel · 05-08-2017, 11:02 AM

Ed if I had your knowledge and help I might still have that car.

I was stubborn as a mule and thought I could tune it myself with almost zero experience or knowledge about EFI tuning.....It was quite a challenge just getting it out and running reasonably well....

Great cars to drive, but tough to learn how to tune without some help or guidance.

Once those cars lost their own classes and the HP kept getting hit I sold it.

pbp1 · 05-08-2017, 11:26 AM

225#s per hour required to support 500hp with a Brake Specific Fuel Consumption of .45

One gallon of Gasoline weighs about 6#s.

225#s per hour = 37.5 Gallons per hour, which equals .625 gallons per min.

This is the minimum fuel volume required to support a 500hp engine.

Like someone said above, it is dangerous to free flow fuel so proceed with extreme caution. Make sure there are no sparks or open flames while testing.

But to test the output, don't check the fuel flow straight out of the pump because that will not tell you anything. To test, take the return line off of the fuel cell and check the flow there because that is regulated to your set pressure.

To supply the fuel needs of your engine, the return line should fill a fuel jug up to the 2 gallon mark in about 3mins, 12 seconds (3.2 Mins).

I got this from calculating 2 Gallons divided by .625 Gallons per min = 3.2 mins.

Bear in mind that this is the minimum required fuel flow. If it takes 3 mins and 12 seconds to flow 2 gallons, your flow is way off.

Also, the voltage drop you are seeing when your fuel pump is running is evidence that the pump is going bad! Need to send your pump in for service and replace the filter. Also, make sure that your pre-filter (before the pump) is 100 micron stainless screen and not the 10 micron paper filter. The 10 micron filter must go after the pump.

Rich Biebel · 05-08-2017, 12:19 PM

Good advice and info.

Absolutely true about not having a filter on the inlet side of the pump that is too restrictive.....

05-07-2017, 07:18 PM	#1
Kdw1403 Member Join Date: Nov 2016 Posts: 206 Likes: 49 Liked 68 Times in 22 Posts	Fuel flow how much fuel should a fuel pump for a fuel injected motor free flow per minute? can i take mine fuel line off at the fuel rail and turn on pump and measure how much fuel it pumps in a minute. Actually i only do it for 20 seconds and times that X 3.. old time way. May not work with fuel injection. Is my math correct that if a aeromotive A1000 pump flows 600lbs per hour would that be 96.77 gallons per hour (gph)? If my math is correct wouldn't that be a little less than the old holley blue pump?

05-07-2017, 08:19 PM	#2
Buick6 Junior Member Join Date: Feb 2015 Location: Florence, SC Posts: 84 Likes: 16 Liked 16 Times in 7 Posts	Re: Fuel flow In all honesty, if I were you I'd call the Aeromotive tech line and discuss your fuel delivery problems and get some recommendations from them. https://www.aeromotiveinc.com/tech-help/

05-07-2017, 08:30 PM	#3
Rich Biebel VIP Member Join Date: Jun 2007 Location: Northern New Jersey suburbs Posts: 2,314 Likes: 25 Liked 544 Times in 213 Posts	Re: Fuel flow It's pretty dangerous trying to flow test a high pressure pump to me like that. I had an LT-1 EFI powered car and it had an Aeromotive A-1000 pump. It had a Paxton pump previously that failed the first time I raced the car. I replaced it with and The Aeromotive was exactly the same. With 24lb injectors I ran some 10.50's in good air back in 2006. The same car has run 10.20's and probably still has the same pump and fuel system. I ran 50lbs pressure and experimented with higher pressure once....It slowed down. I have an all Aeromotive fuel system in my dragster and their stuff is excellent. The design of that pump has magnets epoxied to the outer housing. It has brushes and an armature. If your reading very low pressure and voltage running the pump I would pull the pump out and I would take it apart and inspect it or bench test it. You could power it and pump a fluid less volatile than gas.....mineral spirits..... __________________ Rich Biebel S/C 1479 Stock 147R Last edited by Rich Biebel; 05-07-2017 at 08:39 PM.

05-08-2017, 09:45 AM	#4
Ed Wright Veteran Member Join Date: Mar 2005 Location: Sand Springs, OK Posts: 8,132 Likes: 896 Liked 390 Times in 170 Posts	Re: Fuel flow Rich, raising the fuel pressure makes your air/fuel richer, if you don't lean it back down in the ECU. I found six hp, in A-B-A testing on the dyno raising my fuel pressure from 45 to 60 psi, with the air/fuel tuned back to the same values with both fuel pressures. (Be certain to enter your new injector flow rate with the new fuel pressure) Nothing else changed in the ECU. After tuning the A/F ratio back to the numbers that made the best power at 45 psi. To verify it wasn't something else did it, I put the 45 psi tune back in the ECU, made another pull, lost my new 6hp. Turned it back up to 60, put the 60psi tune back in it, got my new 6 hp back. Same 13.1-1A/F both ways. Your results may vary. __________________ Ed Wright 4156 SS/JA Last edited by Ed Wright; 05-08-2017 at 09:48 AM.

05-08-2017, 11:02 AM	#5
Rich Biebel VIP Member Join Date: Jun 2007 Location: Northern New Jersey suburbs Posts: 2,314 Likes: 25 Liked 544 Times in 213 Posts	Re: Fuel flow Ed if I had your knowledge and help I might still have that car. I was stubborn as a mule and thought I could tune it myself with almost zero experience or knowledge about EFI tuning.....It was quite a challenge just getting it out and running reasonably well.... Great cars to drive, but tough to learn how to tune without some help or guidance. Once those cars lost their own classes and the HP kept getting hit I sold it. __________________ Rich Biebel S/C 1479 Stock 147R

05-08-2017, 11:26 AM	#6
pbp1 Junior Member Join Date: Mar 2013 Posts: 80 Likes: 12 Liked 27 Times in 6 Posts	Re: Fuel flow 225#s per hour required to support 500hp with a Brake Specific Fuel Consumption of .45 One gallon of Gasoline weighs about 6#s. 225#s per hour = 37.5 Gallons per hour, which equals .625 gallons per min. This is the minimum fuel volume required to support a 500hp engine. Like someone said above, it is dangerous to free flow fuel so proceed with extreme caution. Make sure there are no sparks or open flames while testing. But to test the output, don't check the fuel flow straight out of the pump because that will not tell you anything. To test, take the return line off of the fuel cell and check the flow there because that is regulated to your set pressure. To supply the fuel needs of your engine, the return line should fill a fuel jug up to the 2 gallon mark in about 3mins, 12 seconds (3.2 Mins). I got this from calculating 2 Gallons divided by .625 Gallons per min = 3.2 mins. Bear in mind that this is the minimum required fuel flow. If it takes 3 mins and 12 seconds to flow 2 gallons, your flow is way off. Also, the voltage drop you are seeing when your fuel pump is running is evidence that the pump is going bad! Need to send your pump in for service and replace the filter. Also, make sure that your pre-filter (before the pump) is 100 micron stainless screen and not the 10 micron paper filter. The 10 micron filter must go after the pump.

05-08-2017, 12:19 PM	#7
Rich Biebel VIP Member Join Date: Jun 2007 Location: Northern New Jersey suburbs Posts: 2,314 Likes: 25 Liked 544 Times in 213 Posts	Re: Fuel flow Good advice and info. Absolutely true about not having a filter on the inlet side of the pump that is too restrictive..... __________________ Rich Biebel S/C 1479 Stock 147R