APD*98SS

Anyone experience that a boost referenced fuel pressure regulator cant handle a second pump coming on without spiking fuel pressure above 80psi?

i.e. Primary pump on speed controller, second fuel pump on hobbs switch. Under 5# of boost secondary fuel pump comes on and spikes fuel pressure. Primary Aeromotive A1000 can't handle 60psi alone.

Do I simply need a larger single primary pump or is my regulator the issue?

Old Geezer

iTrader: (3)

Could it be, that the return line is not of sufficient size?
A bit about how the system is plumbed, and specific parts used, may help.

APD*98SS

I have the Rick's Hot Rod Shop Stainless steel tank with two internal Aeromotive A1000's. Two internal 100 micron filters feed to -10AN lines through one way check valves. From there -10AN y block to one -10AN feed line to the engine compartment. From there a -10AN to -8AN y block split to two fuel rails. The fuel rails exit to both sides of the B.R.F.P.R. The bottom of the regulator is a -8AN all the way back to the tank.

lethal93ta

what for regulator do you have on there? the A1000 regulator only has a 6 an line out the bottom so that would restrict the flow and it couldnt handle 2 a1000s. the pro series 13110 could handle the flow. a A1000 should be good for 800HP on FI car, with 2 a1000s tho I would think you should have a 10 return line they want a 10 return on an eliminator pump with the pro series 13110 regulator.

APD*98SS

I have the 13110 Pro Series Regulator. However I have trouble seeing 60psi of pressure on the primary A1000 which is speed controlled even if I flip the switch to go full voltage. It barely holds 58-60 psi and as soon as I hit the gas on moderate acceleration the pressure dips to about 45psi. Is it possible a single A1000 is not sufficient for my setup? I have adjusted the speed controller to go full throttle at just about 1700- 1800 rpm. I am truly debating following Bob's suggestion along with other threads I have read on simply having a single pump that flows suficiently for my application like the Aeromotive 11104. My take already has provisions for two -10AN fittings. Instead of using them both for feeds I can use one for feed and the other for a return. And one pump means no more fuel spikes no more black smoke under boost and no more ugly a*s VE Tables. What do you think???

Old Geezer

iTrader: (3)

I agree. I use the 1000 reg and 1 pump on my Buick... Makes about 850FWHP. Would likely need the pro series if I leaned on it much more.
A quik test for the return and reg flow capacity:
Turn on the pumps, attempt to lower the Fp by about 5psi.. Goes, UR OK. Not, you need to look at the reg,[As mentioned by Lethal93], and lines, location of the return at the tank, etc.

lethal93ta

how much power are you making? maybe the 13110 regulator is to much for the car its letting to much fuel return when only 1 pump is on, when both are on its to much for the 8 an line you should have a 10. with only 60 lb injectors and your still seeing black smoke I would think your probably around 700-750 HP 1 a1000 should do it.

lethal93ta

the a1000 system wants a 10 an line feeding the pump witch you have, to the a1000 regulator with a 6 return it could be that with teh bigger regulator and return line to much is going back then when the second pump comes on the 8 an line you have isnt enough sence they want a 10 an return line with the 11104 set up. I would think that 2 a1000s would move more fuel than 1 11104

your best bet might be to get a 11104 pump sence you already have the regulator for it just up your return line size to a 10 your feed to the pump to a 12 and the bigger filter before the pump

APD*98SS

I originally had a 13101 regulator and Bret over at Aeromotive told me that it could not handle the 2 A1000 pumps. the design of the two pump setup is all Aeromotives'. I only followed his recomedations from my original setup. Ever since the two pump deal, things have never been 100% right. I have attached pictures of my oroginal setup.

lethal93ta

di you ever run it with the 13101 and just 1 a1000 pump?

APD*98SS

I have to pose this question: If you have adequately sized fuel feed and return lines along with proper fuel pumps and regulators that match your setup should fuel pressure remain constant no matter if the individual fuel pupms are triggered in series, parrallel, or individual triggers based on boost levels???

APD*98SS

Yes I ran it that way when I had a D1SC blower and before the motor was stroked, and fuel pressure was fine. It never leaned out with SVO 42#'ers; however, I was told that my current fuel system would be inadequate with the larger blower along with the stroked 382.8 cubic inch motor. So I made the switch.

lethal93ta

I would call aeromotive, but my thoughts are that the regulator is to much for just one a1000 its letting to much fuel return.that why you cant get enough pressure even with the controler switch on. when the second one kicks in the return line isnt big enough to handle all the fuel. I would still think a 11104 pump would be better than trying to mess with what you got now.eather way you should upgrade your return to a -10 line.

V6 Bird

iTrader: (15)

Is vacuum hooked up to the regulator from the blower? If so, the pumps are doing what they are supposed to. I dont see your question here.

V6 Bird

iTrader: (15)

Is this pressure set with vacuum disconnected or connected? Cruising around after the pressure is set the car should see less then 58. Once you are out of vaccum pressure should increase 1psi per lb of boost seen at the regulator. Its a 1:1 regulator.

V6 Bird

iTrader: (15)

Your sump has 2 fittings in it at the rear. They are both to feed. Not one for return and one for feed. It doesnt work that way man.

Its gonna go black with 80psi on the gauge. The vaccum is no longer there as the regulator is under boost and supplying the fuel. Sounds to me that the system is working 100% as advertised. After all, think about what a BOOST REFERENCE regulator is supposed to do. Supply more FUEL under boost. If the black smoke bothers you, fix the tuning some. Black smoke will never go completely away but adjusting the injector tables will fix some of that issue. You could ditch the boost reference FMU setup and do it all on demand via the PCM. I dont suggest this way but it can be done.

onfire

iTrader: (17)

If you street drive a lot, I would not go with a super large single pump since you will return a lot of fuel to the tank while cruising....and the fuel will get hotter and hotter.

How much boost are you running?

I have Rick's tank also, but designed it for two 044 Bosch pumps. One runs all the time, one kicks on at 5psi via Hobbs. Brought two -8's to a Y. Single -8 to another Y at the rails. Split into to -8's at the back of the rails. A -8 from the front of each rail to a WELDON brfpr and a single -6 back to the tank.

Single Bosch pump holds a steady 70psi at idle, then ramps up 1:1 via boost up to 90psi to push enough fuel through the 60lb Mototrons.

I'd try a WELDON regulator first if it's spiking to 80psi at soon as the Hobbs kicks in...easy to do and easy to sell a regulator if it does not fix the problem.....some regulators can not handle the kind of volume two Aeros will hit with.

APD*98SS

To the first question, V6 Bird; NO the vacuum line is not hooked up at this time. So the fuel pressure should be at a constant 60psi right???

Secondly, to Onfire; when both pumps are on you do you have any issues with the return line inadequate for that much volume in a -6AN line???

FInally if a speed controller is used with the Eliminator pump that should resolve the overheatig issue don't you think???

APD*98SS

[QUOTE=V6 Bird]Your sump has 2 fittings in it at the rear. They are both to feed. Not one for return and one for feed. It doesnt work that way man.

I was attempting to solve an issue on moving to one single pump. I understand the tank has two (2) outlets or feed lines, however since the Eliminator Pump requires both -10AN feed and return lines to prevent additional welding and or cutting on my tank I improvised in placement on what was available to use without further modification. With that being said, do you think it would work???

onfire

iTrader: (17)

If you do the calcs, it's not even close to being a problem.....a 10psi restriction is meaningless when you're turning a regulator up to +50psi