question about alternators.

[Intensity 10+ year member]

i have a 140 amp alt.. is this enough for a kicker 1250.1 or do u think id need a heavy duty batery or even a new alt?

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[PyroBob 10+ year member]

I believe the rule of thumb is one amp for 10 watts, plus 36 for ECU controls, and 10 for extras (lights, etc.). So, if your amp averages 950 watts, your money.

 

[thehardknoxlife 10+ year member]

I believe the rule of thumb is one amp for 10 watts, plus 36 for ECU controls, and 10 for extras (lights, etc.). So, if your amp averages 950 watts, your money.

Somehow that doesn't pan out.

 

[thehardknoxlife 10+ year member]

i have a 140 amp alt.. is this enough for a kicker 1250.1 or do u think id need a heavy duty batery or even a new alt?

Yes it is..... A new battery wouldn't hurt.

 

[Chevyaudio 5,000+ posts]

I believe the rule of thumb is one amp for 10 watts, plus 36 for ECU controls, and 10 for extras (lights, etc.). So, if your amp averages 950 watts, your money.

nah...that really doesnt work.

the really only accurate way to tell is to get a clap meter and measure the current draw of your amp, and see what it does.

but im my opinon I think you will be fine, with that alternator.

 

[PyroBob 10+ year member]

Hmm, sorry then, I thought that was considered OK.

I suppose when I do it, I look at the alternators idle output, as opposed to it's max rating. I've never had problems that way, but it's possible thats a coinci...coinced...I got lucky.

 

[johnecon2001 5,000+ posts]

Hmm, sorry then, I thought that was considered OK.
I suppose when I do it, I look at the alternators idle output, as opposed to it's max rating. I've never had problems that way, but it's possible thats a coinci...coinced...I got lucky.

Your formula is kinda... weird.

different cars draw more current than others. You can't just use "a rule of thumb".

 

[iceteebone 5,000+ posts]

i had some minor dimming when running a lanxar opti2000D at 1500 watts and a pg tantrum 600.4. you may or not need one. do the big 3 and see.

 

[Johnny Drama 5,000+ posts]

A=W/V

1200w/13v(safe number)=92a max draw

alts have ~40% reserve

140(peak)*.40=56a reserve peak

idle is more like 70a sooo...

70(idle)*.40=28a @ idle

You may have dimming at idle if you listen to test tones all day. While driving you may also see dimming if you listen to tones. If you dont listen to tones you could simply install it and find out if you have dimming. If you do, upgrade your wiring then maybe get a better suited alternator.

 

[Mr. Opportunist 10+ year member]

Hmm, sorry then, I thought that was considered OK.
I suppose when I do it, I look at the alternators idle output, as opposed to it's max rating. I've never had problems that way, but it's possible thats a coinci...coinced...I got lucky.

i have a 275a peak(2.5k) and 140a idle my lights still dimmed w/ big 3 in 4/0, and a yellow top running 1 pbx 3000d....

 

[iceteebone 5,000+ posts]

i have a 275a peak(2.5k) and 140a idle my lights still dimmed w/ big 3 in 4/0, and a yellow top running 1 pbx 3000d....

that's some large wire skeeter

 

[Mr. Opportunist 10+ year member]

that's some large wire skeeter

i know try running it to the trunk //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[PyroBob 10+ year member]

Your formula is kinda... weird.
different cars draw more current than others. You can't just use "a rule of thumb".

That's true, I hadn't thought that through very well. 36 amps is what my old truck drew.

Well, thats why I come here...to get all the facts straight!

Thanks guys.