#11289, "RE: question and idea about capacitors" In response to Reply # 0
A capacitor is not a "battery" at all. Think of a capacitor as the resivoir behind a dam. Power comes into the capacitor and it "fills up" with a charge. Then it's output is regulated at a consistant voltage.
Now, when there is a higher requirement for power on the output side that is not being delivered by the input side then some of the reserve power is sent out to accomidate that need.
On the same token whenever there is a surge of power from the input side the "reservoir" absorbs the surge and still only lets a regulated voltage out to the unit you're powering.
So if you put a cap on your fuel pump it wouldn't really help much unless you're getting horrible voltage spikes or extreme underpower to the pump. I'd say don't waste your time.
#11292, "RE: question and idea about capacitors" In response to Reply # 2
I would think so, but you need to find a cap that runs 14v. I would call radio shack with the specs of the pump motor and see if they have a .25-.50 fared cap that would be compatible.
#11293, "RE: question and idea about capacitors" In response to Reply # 3
a car audio cap would put out 14.4v, but I think the real issue is your relay or something. You shouldn't be getting a "major voltage drop" which would require capping it.
#11294, "RE: question and idea about capacitors" In response to Reply # 4
Originally posted by a_miller_76 a car audio cap would put out 14.4v, but I think the real issue is your relay or something. You shouldn't be getting a "major voltage drop" which would require capping it.
actually we all do. Its not that uncommon to get considerable variations across the fuel pumps voltage. Its the main reason I did the fuel pump re-wire mod and even with that I can still hear a difference across the primary and Hahn pumps when i do something in the car to stress the system, ie- turn on the carputer, turn on the headlights, turn on the A/C. etc...
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#11295, "RE: question and idea about capacitors" In response to Reply # 5
Originally posted by djtrickee
Originally posted by a_miller_76 a car audio cap would put out 14.4v, but I think the real issue is your relay or something. You shouldn't be getting a "major voltage drop" which would require capping it.
actually we all do. Its not that uncommon to get considerable variations across the fuel pumps voltage. Its the main reason I did the fuel pump re-wire mod and even with that I can still hear a difference across the primary and Hahn pumps when i do something in the car to stress the system, ie- turn on the carputer, turn on the headlights, turn on the A/C. etc...
#11296, "RE: question and idea about capacitors" In response to Reply # 6
..
yea i figured this would work
got the idea from seeing the MSD fuel pump booster. i re-wired my pump too, but thats not good enough for me. i tapped the power line down at the pump, and it didnt make me very happy at idle. doesnt get enough power in my opinion.
like i said, fuel pumps are rated on flow for how many volts they run at....something to think about with a strained system like most udp driven 420a's....
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#11297, "RE: question and idea about capacitors" In response to Reply # 7
The other thing to consider, Josh, is it an extended drop in power or is it a flutter? The reason is a cap will discharge rather quickly. They're only used for quick compensation (such as a bass hit in your stereo) and not really designed for keeping something at 14.4v constant for longer than a minute or two at the most. Once the reserve is gone then it's just going to flow straight from source to output, so whatever comes in goes straight out.
#11298, "RE: question and idea about capacitors" In response to Reply # 8
if you are getting any kind of voltage fluctuation, the first thing you should do is remove the ground and clean/sand it. im not sure if thats part of the re-wire or not (been a while since i read the tutorial). if you want to add a cap, a 0.5 farad should do the trick. add it inline as close to the pump as possible. the pump draws very little amperage (comparitavly) so it wouldnt take much to keep the voltage even.
#11350, "RE: question and idea about capacitors" In response to Reply # 9
just get a small motorcycle battery, put it on a solenoid off ur ignition, a charger and wire the pump to that, the pump will ahve its own independent source of power
I just wish my car was as fast as it was loud. people tell me i should use my sub to push it, it might go faster.
