battery vs alternator

Ahh - sadly - I think we've reached an impasse.  Clearly - none of us can 'win' the point.

Anyway - I think I'm our only resident law student, so I do want to point out that ALL of our 'evidence' entered into this thread falls into the in-admissible category of "hearsay" - as in unsubstantiated, unscientific obseravation that is nothing so much as a single person saying "I saw this this and this.." in a second hand manner, without witnesses or corroborating evidence.

I think heamph, myself, bronco, and KP are all guilty here - we clearly can't work this out saying "I saw X, Y, and Z from my Optima..." 

Anywho - I really, really wanna get to the bottom of this.  I think the12volt should at least have some consensus among our more active members.. to many posts deal with this issue and I clearly can't run behind heamph - or he behind me - arguing this stupid point.

I'm gonna find definitive answers we can all agree on.

You can practice all the law you want, 85% of what you just posted is blatantly asinine and has nothing to do with the thread. 1/3 of the posts on this entire site are opinion, usually based mostly on personal experience with a certain product.

"...in-admissible category of "hearsay" - as in unsubstantiated, unscientific obseravation that is nothing so much as a single person saying "I saw this this and this.." in a second hand manner, without witnesses or corroborating evidence." - wth? Who's judging this whole thread - where's the jury? I don't remember who the hell my client is even? If I'd have know this was a court of law, I'd certainly have come more prepared; oh, wait, I'm only 21 years old have never taken a cousre in law - but I think I've hung fairly well with someone who's supposedly our leading law "expert"...

Look, all I'm saying is that most of what people advise is going to step from personal experience, unless it is a post linked or quoted from some sort of research. There's nothing wrong with personal opinion, as most people coming to forums like this are in fact asking for it...

-Matt

Wow.  And here I was *trying* to be pragmatic.

Um.  No - you haven't really hung with me - we haven't really engaged over the course of this thread so I think you just like to follow my posts around and be disagreeable.

Jury?  I dunno - agreement - or at least some general consensus - on a quantifiable question?  Jeeze dude.

Actually - and if you can't see this I certainly cannot hope to get the point across to you - this is a sort of neato argument because it *is* quantifiable.

Yikes! Sorry dude.

So where were you planning on getting an HO alt from anyway?  This is sort of the critical factor in whether or not you should - uhh - purchase one.

Hopefully all the pointless arguing is over with... I'll try to sum this up for you.

If you'll be using a lot of electrical components (A/C, heater, etc...) in the car while the system is turned up, then i'd recommend the HO alternator (the largest reputable name you can afford), then a nice battery or two (depends on if you'll be listening with the car off for long periods of time). Otherwise, if you're smart about it, the Big3 and a nice battery will be good for you. I've got about 90amps worth of system fusing AND two Yellowtops (in parallel, no isolator or the such) on my factory 105a alternator (Big3 in 4g of course...) with NO headlight dimming or voltage drop issues.

Gosh, I think people just like to argue... Oh, and the word is truthiness. It means to state your opinion as facts without any evidence.

friskysquirrel, for a 10 y o Escort and for what you've described as your system, you could probably just buy a fresh upgraded battery.  A black top...like  the original...

...and it depends on whether a fresh new battery was a part of this upgrade.  Also be sure to test, to be sure, that resistance is minimal from the amp's ground connection to the source.

All this battery BS and nobody's answered the question worth answering -- according to my math it's closer to 3A/sec, and that's not accounting for ESR OR ESL.

BTW - if it's going to be deep cycled, yellow, if not red -- why does it have to be so complicated?

It will depend on the car's stock electrical demand and your listening habits.

I used to drive an '88 turbo Tbird.  Stock alt was 75A and it was widely recognized that the alt was undersized w/o aftermarket electronics --

however, being the hard headed person that I am I proceeded to build a ~1000w rms sound system.  At idle it struggled - especially when the electric radiator fan(s) were running.  However, during normal driving it maintained 13v+, and it ran like that for about 2 yrs before the alt finally died.  It had 226k on it at that point.

I replaced it with a 110A and it was more than sufficient.