Do I need a HO Alternator?

You should be fine with big 3 and another battery.

you may nave to recharge the batteries every now and then .but you should be fine power wise for the 2 amps

do ohms law to figure out your current draw and that will tell you everything. I think you will be fine with an extra battery.

Won't need a ho until 3k up

Well it depends, lets explore:

1) You have one 12 volt battery with enough juice to run your audio with car running for at least 15-30 minutes, then your car can't hold a charge anymore.

2) You have two 12 volt batteries with enough juice to run around an hour or so. Then your car can't hold the charge anymore.

Really your better off buying a higher output alternator. Because an extra battery just prolongs the inevitable when the cars current alternator can not keep up with the loads.

Easiest way I suggest is to find a higher output alternator that your cars manufacturer makes, and one thats closest to the vehicle, then modify and custom mount it properly.

I own a 1996 Beretta, I run 500 watts of lights, then the AC which runs 2 engine cooling fans and then the cabin fan, then the audio system pulls quite a bit.

I had 105 amp alternator and my battery died 10 miles later.

After I made a bracket mod, I installed the 3400 v6 140 Amp alternator on my 3100 v6 and now it works just fine. But I had to figure out the wiring to turn it on.

Just shows that if your willing to turn your electronics off and let it charge up a bit, then you can get away with the extra battery.

But A higher output alternator is the best choice. Your car battery will also last longer as well, and you won't have to worry about not having enough to restart the car later.

Well it depends, at some point, the batteries will have to be charged back up is the alternator can not keep up with the demand.

Are you willing to ad an extra battery and charge the car up at home if needed? Or do you want to get a higher amperage alternator which will not require a second battery because it can maintain sufficient output?

Its up to you, I would find the maximum consumption of your electronics on the car, then compare that to the maximum output of the vehicle.

Voltage = Current * Resistance.

Watts = Voltage * current.

Find your wattage consumed on average of your things, find the wattage supplied.

Then go from there and compare how much time a second battery will allow you to go before you have to turn your toys off and let the car recharge.

Usually people add a second battery to help with the rapid current spikes that are required, and their alternator can keep up in between.

It is your choice.

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It is not necessary to buy an aftermarket HO alternator. Any higher output alternator can work, just look through the different manufacturers designs and find one with a case that is close enough to work with some modification. You can probably find a descent used one at the junk yard even. It is also possible to find a way to turn it on and wire it up to work with the vehicle, and to also change the pulley size and type as well as its fan blade so it works.

My 1996 Beretta Z26 now has a 140 Amp Alternator in addition to my 950 CCA battery.

I did consider a second battery, but I decided to get a higher capacity battery.

I did also consider an audio capacitor for my amp, but its not needed. I have a relatively weak amp only 300 Watts RMS output. I should have higher, but its sufficient for my needs as My bass is low, I don't like it really loud.

Here is a link to my alternator modification/findings if you want to read it, however it is specific to my vehicle:

Beretta.net • View topic - RENAMED & SOLVED - CS130 to CS144 Alternator upgrade (INFO)

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EDIT:

Okay I did some checking:

http://www.qualitypowerauto.com/catalog.php?item=470

I see the type of alternator your vehicle takes.

Here is the CS130 and CS144 GM alterantors that are a start:

http://www.google.com/imgres?q=CS144+alternator&um=1&hl=en&tbo=d&biw=1600&bih=756&tbm=isch&tbnid=WGQCc5LRi6dCYM:&imgrefurl=http://www.s10forum.com/forum/f106/bigger-alternator-upgrade-368983/&docid=kS5VJ77GvoLFTM&imgurl=http://www.syphoon.com/albums/album04/IMG_1844.sized.jpg&w=640&h=480&ei=O7XSUOAPhePSAcrTgaAE&zoom=1&iact=hc&vpx=350&vpy=267&dur=2462&hovh=194&hovw=259&tx=122&ty=80&sig=116747642432849148954&page=1&tbnh=135&tbnw=178&start=0&ndsp=34&ved=1t:429,r:10,s:0,i:117

These come in several different case mounting options, classified by vehicle. The CS130 alternator might be the right size if you get opposing mountings like your alternator has.

The CS144 alternator is physically larger, so maybe the offset mountings might work there.

Here is the 2 opposing mounting versions of the CS130 GM Alternator side by side:

http://www.google.com/imgres?q=CS130+alternator&start=73&um=1&hl=en&tbo=d&biw=1600&bih=756&tbm=isch&tbnid=YJJttmAaIClMFM:&imgrefurl=http://www.rx7club.com/1st-generation-specific-1979-1985-18/105-amp-alternator-swap-how-%2596-gm-cs130-504471/page4/&docid=7hjedU3rVlkq3M&imgurl=http://www.rx7club.com/attachments/1st-generation-specific-1979-1985-18/239433d1180047379-105-amp-alternator-swap-how-%252596-gm-cs130-dscf0005_edited-jpg&w=1029&h=687&ei=E7bSUKncMOW40gHjmoDoDQ&zoom=1&iact=hc&vpx=404&vpy=359&dur=1400&hovh=183&hovw=275&tx=143&ty=117&sig=116747642432849148954&page=3&tbnh=134&tbnw=224&ndsp=45&ved=1t:429,r:12,s:100,i:40

In the photo, you can see them, the one on the right looks close to your vehicles alternator, with the proper pulley and wiring, it can be made to work.

Selecting the proper bolts and maybe some washers to properly space it parallel so the belt goes on the pulley and it can be good to go.

Then you would have a 105 Amp max output as opposed to your current factory 80 amp max output.

If you need more, then the CS144 is an option with 140 Amp max output, just find one that fits, like I found the CS130 with a housing bracket close to yours.

And the best part is at the auto store or junk yard you can pay something like 80-140 dollars instead of lets say 400 dollars for a custom HO alternator, maybe 180 dollars, I'm optimistic.

Anyways, its a path you can chose to take. All I can tell you is on my 1996 Beretta the 105 Amps is just enough on the factory vehicle, so I had no choice but to install the 140 amp output alternator.

You only have 80 amps output. Your alternator is probably just enough to run that vehicle and all its electronics on at once, you add your audio system and you'll probably be lacking, and you'll probably need a larger alternator.

But do the math first, and see if you do, and then see what size you need so you don't have to mod it again if you ever have to go larger. Which you can still do if ever needed.

Just some info to throw out there. I hope this helps.

If you chose to modify your car for the higher output alternator, take the time to do it right and any future replacement alternators will bolt right on.

Also, you might have to either increase or decrease the belt size on your car, that however is going to be trial and error to what works best.

My car My belt needed to be an inch longer, but for now I am getting away with the same belt, it just has more tension on it as the pulley is a slight bit larger and the alternator is physically larger so the pulley is sticking away by a little bit.

It is pretty common practice on a lot of Toyotas to swap over to a GM CS130 alternator, it is a relatively cheap upgrade, and could possibly be very easy. From reading, it seems like your alternator is a 4-pin, same as many CS130 case alts, from 4.3L V6's mainly. You could probably buy a fried alt pretty cheap or grab one from a junkyard, and do a mock up, if it would fit the mounts, and wiring, it would be relatively cheap to get to 100+ Amps, and it is a lot easier to find a used HO CS130, usually around 200$ for 220-250A.

Won't need a ho until 3k up

Click to expand...

Just because you are trying to sell batteries on this board does not give you the right to give out knowingly incorrect information.

How would an 80 amp alternator keep 2 batteries charged and provide enough power to run the rest of the car, it cannot is the answer.

I bet if you stopped selling batteries and started selling alternators all of a sudden you would be telling everyone that they do not need a second battery and they just need one of your alternators.

Also I have around 2,000 watts

HO Alt

Crappy Walmart battery

voltage stays over 13

[quote name='>>SQL

How would an 80 amp alternator keep 2 batteries charged and provide enough power to run the rest of the car' date=' it cannot is the answer.

I bet if you stopped selling batteries and started selling alternators all of a sudden you would be telling everyone that they do not need a second battery and they just need one of your alternators.[/quote']

Here here, You are right about adding batteries NOT being the correct answer, at least for 95% of us.

But just to clear things up. Alternator's keep up with electric demands, or try too. Adding another battery does not increase demand by itself. Turning it up loud is what increases demand.

The only reason to have extra batteries is if your doing competition stuff, or just want to turn it up high for short periods of time.

The Best option is to put a amp meter on your alternator (or even on the + lead going to your amps).

There is no reason to be guessing about what your electrical demand is when measuring is so easy.

Personally i just use a portable $50 RMS digital clamp-on amp meter. Then turn the most demand music I like, play to the max listen level i can stand, and measure what it uses.( also having headlights and fan blower on) If that measurement is higher than my alternator can put out. Then look it buying a HO alternator or not playing the music that loud.

[quote name='>>SQL

How would an 80 amp alternator keep 2 batteries charged and provide enough power to run the rest of the car' date=' it cannot is the answer.

I bet if you stopped selling batteries and started selling alternators all of a sudden you would be telling everyone that they do not need a second battery and they just need one of your alternators.[/quote']

I base my opinion on actual experience. I didn't even offer a battery for sale? Now I wouldn't run 3k on an 80 alt but for what the op is trying to do, a big batt in the back would be plenty.