Enough juice?
 

I read a recent post and was kind of curious to general rules of thumb on replacing/rewinding stock altenators and replacing batteries.
I have a 1.5 farad Fusion capacitor with 4 gauge amp kit, but am planning on running an A1300hcq amp which runs 1200w RMS @ 1 ohm. It is a high current amp....
Is the capacitor sufficient for this application? Or is it still going to be rather stressfull on the battery/altenator?
Any feedback is greatly appreciated!

the general rule is that a 1 farad will handle up to 1000 so 1.5 will be just about reaching its limit, but i would go and get a deep cycle battery as well....you could redo you alternator....its really not necessary....i have been doing this for quiet awhile and usually only people in db drag switch out their alternator even then they go with a company made alternator rather then redoing the stock alt....like ohio generators...they are normally rated at like 200 amps!!

P=I(V)

1200W=14(AMPS)

1200/14=AMPS

86 AMPS from that amp considering the 1200 RMS. So lets see. MY alt is at 90 AMPS. Right there the twelve hundred is coming close to what my alt is rated at. With the car running and the lights on. You'll have some dimming.

so the 1.5 farad capacitor is sufficient... i dont need to rewind altenator or replace the battery?

<div class='quotetop'>QUOTE</div><div class='quotemain'>MaDHatteR:
so the 1.5 farad capacitor is sufficient... i dont need to rewind altenator or replace the battery?</div>it would help but its only for power on demand. you can do with just the cap. you could do without the cap. just depends.

i would do the cap and the battery...but thats me!

I'm assuming that's 1200 watts RMS.If that's true(which it should be) then:

1200wrms/.707= 1697wPeak

This means that on peak current demand,the amp will require 1697 watts.That's assuming that you have the sub(s) wired in such a way that will use all the power the amp is rated to put out.

So,your 1.5F cap should just barely make it. wink

Now,in one of my cars I had a factory 100A alternator,and I was pushing a total of 700WRMS on the stereo.With a normal battery,I could only listen to the system with the engine off for about 20 minutes!!After that the car wouldn't start.Then I put in a yellow top Optima,as the primary battery.After that I could crank the system with engine off for close to 1 hour.Also,I used a 1F cap,and I had no dimming of lights or other abnormalities.

For your application I would DEFINETELY use the 1.5F cap and a yellow top,or other deep cycle battery.If these 2 things don't keep you solid,then the next thing would be a higher output alternator.Next step from there would be a secondary battery with battery isolater.

battery isolator works pretty well! but i really dont think you will need that much....is a little over board

i would say get the atlernator regardless. what's the point in a deep cycle battery i you can't keep it charged? But to each is his own. I prefer alternator, battery and caps. then your good up.

in my experience, you dont need the alternator. ive had my stereo in my car for about a year, and my stocker is holding up fine. i just have a digital 15 farad cap and a optima yellow top, and they work fine. i probably will upgrade the alternator when it goes out, if it ever does!!!