how do i know if i need 2 batteries

heres the deal you have heard a few arguments regarding adding and not adding a second battery. they are all true and all false. i say this because everyone is an expert when it comes to something like a vehicles charging system. now if that were true than no question would have been asked. everyone has there opinion. thats the point. there is plenty of things that can be done to increase the amount of power from your stock alt. 1 big thing and is required when adding a ho alt. upgrade the wire going from alt to batt. most cars trucks etc have either 8 guage wire or smaller comming from alt. i was working on a yukon the other day that had smaller than 8 guage wire comming from alt (factory) in that application i upgraded just the 2 foot peice of wire from that like 9 guage to 0 guage fusing it just incase. the difference in that little change was blinking headlights when two 15 were pounding to no longer blinking after wire swop. My point is wire is one of the most important thing to have correct. because wire has resistence. and over a long piece of wire there is voltage loss. to keep voltage loss in a car to a min. do a little over kill on the wire. it aint going to hurt you other than in your pocket. but your amps will have less chance to be starving for power. try both things if you want or dont if you dont want. a cap is used to supply a short burst of energy to a device in its imiediate area. meaning a cap will not do you any real good if it is to far away from the amp that is requiring the biggest pulse draw, for example when your bass hits. But that is all a cap is good for supllying a burst of energy stored in a close proximity to the amp. so that the power needed is there and does not have to travel through the length of the cable. NOw it is true a second battery can help and hurt you., of course if the battery is not used in stock location the best bet is dry cell stinger or other. But one reason it can help you Just like a cap. if you put it close to your item that needs power there will be a loss of power need which caused flickering of lights. in your application your not running all that much so a second battery will probable help you but it will hurt you because it will cost more than 2 and change to do it right. you cant just put a second battery inline with out some type of isolation when it sits. a common way is a 200 amp relay that disconects power to second battery when system is off. you also have diode isolation for additional batteries in cars. but in the audio field that sucks becuase there is a voltage loss over the diodes. The time in which you need isolation the most is when the car is sitting engine off. radio off everything off. what happens with no isolation is the batteries compete. and int he long run loose there power., so isolate it. 200 amp relays are the most common. along with many other devices you can get. BUT if you your inlack of wire guage than a second battery willnot do you any good. 4 guage wire is not sufficient. there is not enough current alowd in 4 guage wire to make a difference. your best bet and maybe the cheapest. go to ebay Get your self some zero guage wire with a 0 guage fuse holder for the battery side as standard. check to see if you can upgrade wire from alt. do it if you can with 0 guage with 4 something.And then get a bigger more powerfull higher rated name brand cap. and most of your power issues will be kept to a minimum if that does not satisfy your systems needs. or go the expesive route. Higher guage wire all around. second battery dry cell., 200 amp relay good terminals for the battery (both) thay make a pac peice that will control second battery and system for when you use system with car off. if you want pictures i have plenty of my car with similar situation I am running 4 amps alpine mrv f540 Kick panels, front door mids. Tweaters on pillers. Alpine mrv f 340 6x9 rears 2 tens on back deck for a three way system Alpine f 320 alpine center channel single din speaker. Hiphonics brutus 1600 A single 12w7 in fiberglass box. three tvs, alarm remote start., gps. and various other things. all this runs on stock 100 amp alt and only a voltage drop of 14.2 to 13.4 is experienced when my system is cranked and bass is going. the way i did my wiring my battery reads the same voltage in the back as the battery i have in the front at all times. meaning i dont experience a big enough voltage loss in my wire to bother me. i have a second battery in the back stinger, with a 200 amp relay have pictures email me.Jon

Installer/Help Technician

---coral springs florida---

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jlord16 wrote: What is the factory alt rating on the yukon??

My Yukon has a 100 amp alternator. Its' the same one that came on the truck when I bought it new in 96'.  I did the big 3 upgrade shortly after I  purchased it. I added 1 battery and have had no less than 3,000 watts rms of audio equipment in it ever since. Right now it is closer to 6,000 watts and I'm running 4 batteries.. It has been almost 10 years and still running strong. My personal experience is what I base my opinions on, not what I read somewhere or was told by a "guru". All the quotes in the world from audio gurus and techheads won't convince me to change it!  It worked for me, am I alone in this conclusion?

Gettin' deafer by the day.......96' GMC yukon-Eclipse CD 5442HU

MA Audio HK4000D-Digital Designs 9515F

150+db with one woofer...DD rules!!!!

Personal experoce counts for the most, but then again some people have bad expericenes.  By no means am i saying a second battery is bad, but other things like the big 3 need to be taken care of aswell as djfearny2 outlined.  Now i have a question, how the hell do u find out what ur stock alt is rated at.  Mine says nuthing about it in the manual specs or anything.  If you do a setup properly with a second battery it will work, the only problem some people ahev is they overlook things or use the wrong parts. Clarion DB36MP

Infinity Kappa Perfect 10"

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ALPINE MRP-F250

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jlord16 wrote: Personal experoce counts for the most, but then again some people have bad expericenes.  By no means am i saying a second battery is bad, but other things like the big 3 need to be taken care of aswell as djfearny2 outlined.  Now i have a question, how the hell do u find out what ur stock alt is rated at.  Mine says nuthing about it in the manual specs or anything.  If you do a setup properly with a second battery it will work, the only problem some people ahev is they overlook things or use the wrong parts.

Probably the simplest way to find out amperage on your alt would be to call an autoparts store and have them look one up for your vehicle. More than likely they will be able to tell you the amperage. Thats' what I did. There may be some where online you could look, but I'm not sure.

Gettin' deafer by the day.......96' GMC yukon-Eclipse CD 5442HU

MA Audio HK4000D-Digital Designs 9515F

150+db with one woofer...DD rules!!!!

djfearny2, i appreciate all your imput thank you alot. I also would like if you could post pictures if not email them to me please that way i have something to refer to thanks. Pmendoza408@hotmail.com Also i saw that hifonics makes a 0/1 gauge wiring and Boss makes one two the price difference is around 30 bucks what would be the best buy the salesmen told me that wire is wire and it would not make a difference. I just wanted to know. Know if i go with to yellow tops or svrs this will help somewhat from what i get but i must also consider a ho alternator where can i get info on this i have a 92 honda accord i went to a auto parts store and they told me that they only carry the ones to replace stock alt not any after market stuff. I also went to a mechanic and asked him if he could make my stock one pump out more juice he said that he didn't do that nore heard of it>? well i just wanted to know a bit. Thank you all for the help.