do i upgrade my alternator?

lost me. So stay with one batter or get a second? and if I get a second what do I do with the first one?

I hope my expression and description is really bad, otherwise I would question the ability of "installers". Ok, not the installers I have come to know, but... (Has that "test/exam" been done yet?) A second battery means another battery IN ADDITION to the first one. According to me, that 2nd battery should be an AGM (because it's "inside" else you want a low ESR = Equivalent Series Resistance; very similar/related to "internal resistance") and it shall be placed near the amp. Why - because caps are bullsh and even a small AGM usually does more than a cap. AND - because a 2nd battery can be drained but you still have your primary battery to crank & start the vehicle. That assumes you have a battery isolator - and for isolators you can chose between expensive and "complex" voltage sensing isolators that require one less wire to find & connect, or a simple, cheap, common "charge controlled" relay. (The latter also as per "me" and like-minded people). If you use one battery, will the audio/amp drain it? If it does drain it, does it matter? (Can mummy or daddy or someone give you it a jump start or pick up the occupants etc?) Or can you fit a low-voltage cutout that ensures cranking/staring capacity? Personally, I like two batteries that are connected together ONLY when charging. If one does fail, I should have the other to crank & start with. (And after starting being able to charge both batteries, or at least get my date home.) And by only being connected together whilst charging, there is no need to worry about whether batteries are "matched" or not. (That also assumes a voltmeter else some way of knowing that a faulty battery is killing the other battery and the system..) Hence, according to me, you keep the first cranking battery. The second (AGM) is placed as near the main load/amp as possible. Or if you do not want that independence, just use one battery. Whether it is the original in the engine bay, or a new AGM next to the amp (that also cranks the vehicle) is up to the customer. Or maybe the normal engine bay battery with a small AGM (~$30) next to the amp instead of a capacitor to help overcome surge shortfalls. It's whatever the customer wants combined with the costs involved. [FYI - I am somewhat sick of people that often sell batteries claiming that batteries can be paralleled - whether "matching" or not and without qualification - despite that many non-battery-sellers seem to suggest "do not parallel" (unless or except...). My latest is that for two paralleled batteries, the one with a collapsed cell will not damage the other. I am having difficulty correlating that with my knowledge and recalled writing of others... But this is from an expert... that sells batteries.) ] So in summary, do whatever the customer wants else what you advise or chose to do.

I understand what a second battery means. My questions was with this system stated and a 190 amp alternator SHOULD I add a second batter to the system or should I just replace my one I have in there now with a really good batter? I know what ESR is and what to look for. I know what battery isolator is and I have installed a few. I understand you questions the MECP exam but at the end of the day this is not all covered and its a shame. I have also been out of the loop for some time now with a new full time job. I appreciate you trying to help me and I apologize that we are having trouble understanding each other. I do a lot of installs but rarely anything of this magnitude. I know its not all that big but it is a lot bigger then the low to mid grade stuff we carry at best buy and we really dont need to worry about power from day to day unless its a civic or something. I will clarify myself. I want to know if I should use two batteries or one given the 190 amp or even maybe a 250 amp alternator I want to know what alternator is the best to go with in terms of amps I should get and a place to get it from. I want to know what battery is a good battery to get being one or two. Like I said before I know a good amount about this stuff but never really applied it real life and now that I am doing my own bigger system I want to get it right and learn. I am looking for expert advice from people have worked with what I am looking for and have learned from trial and error.

A user pm'd me and said what is pasted. Anyone can vouch for the vendors supplying quality alternators? I dont wanna get screwed here. vada_808 Rookie Rookie Joined: June�28, 2009 Posts: 2 Location: United States       Sent: May�31, 2010 at 11:30 AM      Delete Reply To Private Message i would get the biggest alternator you can afford do the big 3 with aleast 1/0 wire. you only need a second or more batteries if you want to play your system extended periods with the car off. for a alternator i would go with http:///Iraggi-Alternator-and-Electronics__W0QQ_sidZ35089818?_nkw=nissan&submit=Search, or http://mechman.com/store/index.php, http://www.ohiogen.com/, http://www.dcpowerinc.com/alternators/nissan.html. if youre looking for a battery i like http://4xspower.com/

I can't comment on alternator suppliers & reliabilities (I just don't know - other than I won't use Bosch.) You only need a bigger battery if the original is too small for whatever reserve time you require (without adequate alternator etc). If your alternator isn't charging enough - the battery has to stay "high" enough to get you through (to a recharge). The lesser the battery discharges, the longer it should last wrt to life time & aging.     You only need a second battery if: (IMO) you need a capacitor to "fill dips" (IMO an small AGM is more likely to be cheaper and superior); Or you want to separate the audio/amp battery so that you have a cranking battery. For low ESR, the battery should be close to the amp. A low ESR battery in the engine bay (and remote amp) is almost useless (other than providing good cranking amps) - the cable resistance to the amp adds to the battery's ESR Hence a low ESR battery near the amp; the "high cranking current" for the starter motor. I can't advise any better without knowing the average power consumptions of the car and of the audio and amps etc; the average power output of the alternator; and the capacity of the battery. Even then it can be difficult (age, temperature, extra loud day). Maybe others can advise?

I'm with oldspark Posted: May 31, 2010 at 11:30 AM , without knowing a lot of other figures I speak in generalities.

I'm also not willing to type near as much so my answers tend to be more to the point and concise.

After years in an international relationship full of chats, I actually hate to type, I would WILL the characters on to the screen with my mind were I able to do so.

Back to the subject . .  as for the PM . .  I second that, but I assumed this was something you already new per your qualifying first post.

Secondly, in the future as far as online etiquette is concerned, if you reveal the contents of a PM for verification, please extend the courtesy of not revealing the SOURCE.

This person sent you the info in a PM for a reason. It's their privilege to remain anonymous with pertinent info.

"I want to know if I should use two batteries or one given the 190 amp or even maybe a 250 amp alternator

I want to know what alternator is the best to go with in terms of amps I should get and a place to get it from.

I want to know what battery is a good battery to get being one or two." - consider info from PM and oldspark

You know a good mfr for second batteries and you know some good resources for where to buy them, anything else you're going to have to make a judgement call about your particular usage\requirements and speak to the resellers about their terms and warrantes etc.

How much is overkill and how much are you willing to spend? . . there's no right answer to this in a forum.

Research > Decide > Purchase > Install > Pass on knowledge

65% > 3% > 2% > 25% > 5%

Just my humble opinion

.

I know just enough to be dangerous. VERY dangerous.

Is that my "May 31, 2010 at 9:30 PM"? .... damned Zulu time LOL! (Rhetorical question; bad config.)    Tried "Dragon Naturally Speaking" (voice to text converter)? I did have it years ago. Anon1 is correct. As usual. Second the etiquette - NEVER pass on who or their email address (use BCC!!) I take the conciseness. Verbose does NOT work. I should stay concise hence reach more.

Hey man your ramblings are pure genius!

Anyhoo, nothing I said was intended as an indictment, admittedly I'm just not as helpful as others for the reasons stated.

I genuinely want to see people succeed at what they endeavor to so and am willing to give anyone my 5 minutes to better the cause.

After all, that's what we're all here for anyways. For the times I seem short in my answers, please don't take it the wrong ways.

I know just enough to be dangerous. VERY dangerous.

Awww shucks! AGAIN! Out intents etc are the same. (Our similar "thinking" is irrelevant per se, but is VERY convenient for readers, and GR8 for me!) I was self-criticising. I know verboseness is counter productive. But I dropped my old "executive" style - first the conclusion then summary, then expansion for the dumb ones (ie, executives; once they get home). But I still expand "as I write". Bad bad bad! I did not take your comments as a crit (not personal or offensive anyway) - merely as your typical SPOT ON assessment. SEE - I was too brief... I have to be verbose else people misunderstand!!! Nah me dork - they fall asleep or die before any misunderstanding...