Need Help With Power Supply

[AMI CUSTOMS]

So I should be looking at my Amps RMS or Peak Watts when trying to dice an Alt.?

4100w RMS / 14.2v  = 288.7A

288.7A + 60A (for the electrical systems) = 348.7A

8200w Peak / 14.2v= 577.5A

577.5A + 60A (for the electrical systems) = 637.5A

So should I look for a 350A Alt. or like two 325A Alt's?

And what size batteries should I get for the back?

be worried. the info in this thread sucks so far.

your math is off because you didnt factor efficiency. you need more like 470amps. dont ever ever ever ever ever ever ever, ever look at peak or max power ratings. they are useless. rms only!!! so a 250amp alt with a higher idle output than a 300amper, with two xs power 2400s plus a starting battery and you will be covered.

I was thinking the same thing then scrolled down and was relieved to see at least one good response.

[AMI CUSTOMS]

Oh and just as a reference, one of the guys on my team runs an RD D9 amp, 5k rms amp all day, off just stock 145 amp alt D3400 underhood and HC2000 next to the amp, stay above 12 volts even when clipping

[RF4LIFE]

Dose anybody know the Efficency of an class AB (T8004) and a class D (T20001bd) amp?

So above he used 80%, let me know if this is the correct math?

4100w RMS / 0.80(%) = 5125w Needed to get the RMS

5125w / 14.2v = 360.9A

360.9A + 60A for system = 420.9 Amp Alt. needed

So for this system (@80%) I should replace the stock 130A Alt. for somthing like a 425A Alt. ?

OR what do you guys think about running a compleat sepreat system? I could run a 360-375A Alt. in addition to the stock 130A Alt. and just run a compleat separate wires back to dual battery's ?

Which would be better? Space is limited so I could only run 1 or 2 extra batteries?

[doodcody]

mechman 270 amp alt. d6500 under the hood and 2 xp3000's in the back. monitor voltage and add another xp3000 if needed.

[RF4LIFE]

should i run the wire/Alt./batt as a separate system than the car, or run them together? And should i replace the stock Alt. or just add to it?

[doodcody]

just leave the wire as it is from the alt to front batt and then wire from the front batt to the back batt's if thats what your asking. i asked mechman if there was a dual alt bracket for my 05 explorer and he said no so i assume its the same for yours. I didnt check with the other companies. I went with a 270 amp alt from mechman, but go bigger if you can find one!

[RF4LIFE]

should i run the wire/Alt./batt as a separate system than the car, or run them together? And should i replace the stock Alt. or just add to it?

[RF4LIFE]

i have heard about running the two batts, amps, and the alt together in a close circuit so there is no interference with the main batt and alt? should i do that or just run them together as one big system?

[doodcody]

i'd run it all together, and it seems most people on here do. I wouldn't be too worried about interference but it's up to you!

[RF4LIFE]

ok, i have two 18 foot 1/0 awg wires should i:

a. Run one as a Positive from the front Batt to the Back Batt(s) and run the other as a Negative from the front Batt to the back Batt(s)

+Wire ground is always better than a Regular Frame Ground

-Current draw (360.9A) may be too much for the single 1/0 awg (350A) Positive

b. Run both as Positives from the Front Batt to the back Batt(s) and just do a regular frame ground

+Dual 1/0 awg Positives should provide more than enough current (up to 700A) for the 360.9A needed

-Regular Frame Ground may not be enough