Aeromotive regulator, two pumps, two pressures?
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From: Dublin, CA
Aeromotive regulator, two pumps, two pressures? I have dual pumps feeding a single -8an line, the second pump is gas pedal micro-switch actuated, and its' relay is connected to the alternator. The primary pump is connected through the stock wiring. Both are Walbro 255lb pumps. I'm using an LS2 fuel rail with -8an fittings and am using the stock feed as a -6an return through an Aeromotive regulator.
I adjusted the regulator to 60psi (engine off, floor the pedal, check pressure, adjust regulator). However when the car is running on the primary pump, the fuel pressure is at 50psi.
Shouldn't the pressure always be at 60psi regardless?
I adjusted the regulator to 60psi (engine off, floor the pedal, check pressure, adjust regulator). However when the car is running on the primary pump, the fuel pressure is at 50psi.
Shouldn't the pressure always be at 60psi regardless? Thread Starter
TECH Enthusiast
Joined: Dec 2001
Posts: 548
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From: Dublin, CA
Thread Starter
TECH Enthusiast
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From: Dublin, CA
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From: Norn Iron
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Teching In
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Lower volume will make less pressure through a given orfice. The orfice would have to shrink in order for the reg to have the same pressure at lower volume. 2 pumps twice the volume = more pressure as compared to one pump.
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From: Norn Iron
If a FPR had a fixed orifice, it would be pretty bloody useless as a FPR !!!!!!
Staging Lane
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I am sorry but it will increase the fuel pressure when the second pump (added volume) comes on. He will also experience a fuel pressure fluctuation if he adjusts fuel pressure with the boost line attached -- the regulator is not in a neutral position.
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From: Norn Iron
He will also experience a fuel pressure fluctuation if he adjusts fuel pressure with the boost line attached -- the regulator is not in a neutral position.
Staging Lane
Joined: Oct 2006
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You are correct (and mine are one of the best out there) -- not to split hairs but....With my pumps (Weldon) I've got many customers that experience these issues when using a secondary pump (stock intank and then bring in a 2015, 2025 or even a 2035). Its that split second (and possibly longer if the secondary pump is large) that can cause or wreek havoc with some ecu's or injection systems.
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From: Norn Iron
I guess its just a case of not selecting the correct parts to get the job done. If bringing a pump with huge flow online as a secondary, then I guess its only normal to have some fluctuations.
With staged setups, there will be a compromise somewhere, unless the secondary pump can be brought online slowly.
I just run my 044's all the time. Saves worrying about stuff like that.
With staged setups, there will be a compromise somewhere, unless the secondary pump can be brought online slowly.
I just run my 044's all the time. Saves worrying about stuff like that.
Thread Starter
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From: Dublin, CA
I do notice pressure bounces about a pound when the secondary pump comes on and the motor is running. I'm measuring fuel pressure at the regulator. I'm using the Aeromotive A1000 regulator, -8an hoses to the rails and -6an hoses after the rails.
