hey i guys i am looking to put in some subs into my car and i was wonderin if yall knew where i could find out how many amps my stock alternator puts out? cause i have a feeling i am going to need to upgrade no matter what. peace

 

ok is there a sticker some where on my car that might tell me the size ?

 

It's either 100 or 110 amps. You won't need to upgrade the ALT. Just get a beefy capacitor to hanlde the dynamic peaks that your system will generate.

DW

 

wrong. caps are band-aids, they dont solve the prob. and SEs have 125A alts.

 

is that 125 at idle

 

Yeah, I guess the Nissan Factory Service manual must be wrong. 110 amps is the most his ALT will have.
And secondly, he doesn't have the problem, he's only anticipating it. A system only needs it's maximmum power at loud volumes when there's heavy bass in the musical material. That's a periodical electrical demand, not constant. I suggest you cap your system first, if you still have trouble, then explore the ALT upgrade.

DW

 

dude, SEs have 125A alternators, donate your money and do the search.

also, lets do some math shall we?

car electrical systems run at 12V
lets say you have a modest amp that draws 50A at full draw.
and lets say that you have a 1F cap.

1F*12V/(50A)=.24s

that is about the length of ONE bass hit. and that is assuming the cap is fully charged which takes time too. so if the cap is fully charged to begin with, after about 4-5s of a bass heavy song, it is totally useless. then lets take a big system that draws 150A, suddenly, that 1F cap is only good for .08s. That is almost TOTALLY useless. If you want to run a big system, you NEED a big alternator. No ifs, ands or buts. Any questions?

 

this thread will be moved.


but you should use optimal battery, and cap you wont have problem. how much you planning to push out of your car? what gauge wires?

 

battery does not help. only reason to get a deep cycle batt is because most systems draw more than the alt can put out, so you start draining batteries. most batteries dont like being drained and recharged so much. deep cycle batts are more tolerant than normal batts to this discharging. and again, caps dont help, they are a way for you to spend more money, well, i suppose they help a VERY small bit, but it is nearly irrelevant. the only truthfull thing you posted was wire gauge. since gauge directly affects the maximum current that an amp can draw.

 

I quote from the service manual and you still dispute it? Funny, I guess Nissan is wrong, then.

DW

 

http://forums.maxima.org/showthread....alternator+125

do you need more?

 

Interesting thread. It doesn't say I was wrong or you were right. All the amp ratings we mentioned are stock. 100,110, and 125, depending on car trim.

Anyways, my 98 Cali SE was specced out with a 110 A ALT, stock

DW

 

thats all I am saying! not all cars have 125A alts, but some do, and you would not budge.