Can I JUST Get a HO Alternator?

[Ali G 10+ year member]

So, I'm thinking for my next install, I'm going to need to upgrade my electrical system. I plan on running a NINe.1, a NINe.2, and a NINe.4... and I'll be running the NINe.1 down to .5 ohms. So, I figured the Big 3 is a must and a second battery... but I don't want to deal with finding a place to mount the battery and having an extra 50 lb battery in my trunk (it is a WRX so I want to Auto-X it and drag race it sometimes).

So, my question is, will just getting a high output alternator and doing the Big 3 be enough to fuel this amp setup, or will a deep cycle battery be a must, too? If I can just get a new alt. how many amps should I be looking for? The NINe.1 can draw 130 amps alone, then the other amps can draw 50 amps a piece.

And if I DO need a second battery, would that suffice without having to drop the money on a new alternator?

And would it be too risky to do the Big 3 and install that setup on my stock electrical system to just see how bad the dimming is, or would it cause permanent damage immediately?

BTW, the stock alternator is 110 amps.

Just looking for some adive here.

Thanks,

Justin

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[johnecon2001 5,000+ posts]

If it were me, I would do the big three and look into that HO alt. The second battery most likely won't be needed but it wouldn't hurt to beef up the original a bit.

 

[knukonceptz 10+ year member]

I am the opposite, upgrade the grounds and add the second battery. Most HO ALTs put out power at higher rpm (over 2500) These days they are getting smarter with smaller pulleys. Lots of people add under drive pulley and well that gained HP but slows the ALT down too.

By buying a similarly sized battery or even a small SVR type battery there is more amperage capacity available. 90% of audio systems do not need an HO ALT for the fact that you do not draw that much currnet every second the car is running. Now if your doing low frequency sweeps non stop or rollin to some bass CD's 24/7 then yes, your stock ALT will not keep up with the demand. Anything over 90A if in proper working order and properly wired will easily support a 200A system with a second battery. Your stock 110A should be fine for the application.

I would add the battery and run with it....$120 optima vs $300 ALT....With the saving buy a voltmeter and watch the savings //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[White Rascal 10+ year member]

A second battery is only good for extended listening with the engine off. Once the engine is running all the electrical equipment gets it's juice from the charging system and not the battery. When the engine is running the battery becomes part of the load on the charging system just like the stereo system.

 

[knukonceptz 10+ year member]

Right, which is why SPL cars have no batteries............since they are running in the lanes the ALT takes care of it all........WRONG.....Everything is connected, your ALT goes to the battery, the battery to the car's Fuse panel and of course our massive stereo's. To say the battery is NOT part of the charging system is like saying your ground wire is not part of your stereo...............To think NOTHING comes from a battery with the car on is not correct.

With a good battery, how many amps at idle do you think the ALT puts out? no accessories on. Just the car running.

The battery is not like a cap, it holds the charge. A cap stores whats available.

 

[White Rascal 10+ year member]

The battery is NOT part of the charging system. The charging system consist of the alternator, rectifier and regulator. If the stereo is drawing current from the battery while the engine is running then the battery will eventually have a shortened life span because it is not charging as it should. I've been involved in car stereo for over 30 years now and I know this right.

 

[knukonceptz 10+ year member]

Ok, so there is not ANY wiring involved in the charging system? Rectifier and regulator are built into the ALT on what 85-90% of the cars on the road today? So then just the ALT is the charging system.....nothing else, how is that a system? Your definition is flawed. A battery is directly connected to the ATL and therefore is part of a system, which connects the rest of the car. It has to be part of something

If the ALT powers the stereo, why dont we connect out wires at the back of the ALT? Because the battery takes up the slack for what the ALT can not instantly adjust to - spikes. Some Ford Regulators are actually delayed to avoid spikes made by the ALT. Additional batteries assist in large consumption of power (Reserve capacity) and they are recharged by the ALT once the demand is no longer present (ie between tracks, when your ordering your food in the drive though, talking to your girl on the phone....etc)

So UNLESS you have the stock ALT @ FULL capacity used 100% of the time a second battery will be very useful. And to get full use out of your HO ALT you need to be at higher rpm, which on most cars when doing 35-45mph they are near 1750-2000rpm max. Freeway driving only I suppose..

Edit - I need recharging myself, foods callin //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[93 saturn sl2 10+ year member]

Get a H.O alt and make sure that you know how many amps it puts out at idle, and do the BIG 3. If you really want a 2nd battery get a BatCap, it is like a 3rd the size of a regular car battery and discharges quick like a cap.

 

[75MonteCarlo 10+ year member]

so if your battery soaks up the spikes in current draw (i.e. heavy bass hits) then it is constantly discharging, and the alt is constantly charging it. The whole point of the big three is to increase the rate at which the battery can charge/discharge in order to keep up with the demands from the system, so therefore wouldn't a heavy capacitor be better than a second battery? Given 5 farads to work with, the caps deal with the spikes of current draw, and recharge very quickly (usually between beats if the wiring is big enough and the alt is putting out enough amperage), taking the strain off the alternator and giving it a more even current draw. In that case a higher output alternator would be great, to keep up with the capacitor draw, without being strained by current spikes from the amp, and still keep all of the other loads in the car's electrical system happy.

An extra battery will provide reserve when the stock alt can't keep up, yes, but if its reserve you need (assuming your playing music with the engine on), then you want capacitors, not batteries, because batteries do not charge like caps do, and all the rapid charging and discharging will wear them down and result in a dead battery in due time (especially in cold climates).

Engine off, yes, you'd want a massive battery bank to supply power to the amps at whatever current draw it needed, but engine on is a different story all together.

I say do this: HO alt, optima yellow top to replace stock battery, big 3 wiring upgrade, and 1.5 farads of capacitor per 1000watts rms of system draw.

Infact, given large cap banks, it's probly wise to wire the caps directly to the alternator, and ground, effectively circumventing a batter alltogether.. although your stereo wouldn't work with the car off..

 

[knukonceptz 10+ year member]

A cap STORES power available, a battery can create ADDITIONAL power. There is a difference. Now if we are designing the perfect electrical system, we would have a HO ALT a second battery and a small cap per amp. That would be the absolute optimum system.

I am not against getting a HO ALT, he has 110A factory ALT that is working fine and probably has a factory warranty. Speaking from the practical point of view, add a battery - $120, IF your ALT does ever take a crap, then upgrade. By adding the battery you can see first hand what happens with the voltage and if the stock unit can keep up.

 

[Johnny Drama 5,000+ posts]

A cap STORES power available, a battery can create ADDITIONAL power. There is a difference. Now if we are designing the perfect electrical system, we would have a HO ALT a second battery and a small cap per amp. That would be the absolute optimum system.
I am not against getting a HO ALT, he has 110A factory ALT that is working fine and probably has a factory warranty. Speaking from the practical point of view, add a battery - $120, IF your ALT does ever take a crap, then upgrade. By adding the battery you can see first hand what happens with the voltage and if the stock unit can keep up.

The problem I forsee with just upgrading the battery is that once the current draw is over the output of the alternator t is drawn directly from the battery. 1, 2, 3, 4...it doesnt matter how many batteries he has, if the alt cant harge what is being drawn they will go dead. Hence the HO alt. I have enough experence and know enough from talking to people I trust to know that I HO alt>a second battery any day (if current draw exceeds output).

Steps I recomend...

1)big 3

2)better battery and HO alt

3)isolator and second battery. Run stereo on seperate battery. (not nessisary)

 

[Prowler573 5,000+ posts]

A cap STORES power available, a battery can create ADDITIONAL power.

No, it can't. A battery is no less a rechargeable storage device than a capacitor. The only thing that 'creates' power in your car is the alternator. Regardless of the path that the available current is drawn across it is all sourced directly or indirectly from the alternator.

There is a difference. Now if we are designing the perfect electrical system, we would have a HO ALT a second battery and a small cap per amp. That would be the absolute optimum system.

Manoman would that be a waste of available mounting real estate. Tsk, tsk. //content.invisioncic.com/y282845/emoticons/nono.gif.eca61d170185779e0921b0faa9704973.gif
I'd go the Big 3 first. This won't increase the capacity of the charging system but it will provide the existing current a more efficient path on which to flow. And keeping in mind the possible Auto-X interests barring the Big 3 upgrade being sufficient an HO alternator would help more in the long run and carry less overall vehicle weight than an auxillary battery would.

 

[knukonceptz 10+ year member]

You guys are missing the point, NO ONE draws 110A of current every second your car is running and an Isolator is an even bigger waste of your money.

A simple example, your car battery has X amount of amperage. Add a cap and you still have X amount of amperage but in different locations. Add a second battery of equal size to your front battery and you now have XX amperage available. Add an isloator and you back to X amperage PER "system"

Yes, you would want to have the ability to charge/recharge your batteries, but can you honestly say you drive 24/7 with every accessory on, maybe in Alaska where they have no sun for weeks on end ok...my point is you do not draw that much all the time and your front amps draw very little compared to the subs, which are not constant either again unless your doing a sweep or Db Drag.

 

[knukonceptz 10+ year member]

No, it can't. A battery is no less a rechargeable storage device than a capacitor. The only thing that 'creates' power in your car is the alternator. Regardless of the path that the available current is drawn across it is all sourced directly or indirectly from the alternator.

Creates was a bad word to use, adds energy available would be better. A cap stores what is already in the system. A battery adds to the system. Yes, bith need recharging.

And I totaly missed the part of his post about Auto-X....DOH

 

[Johnny Drama 5,000+ posts]

You guys are missing the point, NO ONE draws 110A of current every second your car is running and an Isolator is an even bigger waste of your money.
A simple example, your car battery has X amount of amperage. Add a cap and you still have X amount of amperage but in different locations. Add a second battery of equal size to your front battery and you now have XX amperage available. Add an isloator and you back to X amperage PER "system"

Yes, you would want to have the ability to charge/recharge your batteries, but can you honestly say you drive 24/7 with every accessory on, maybe in Alaska where they have no sun for weeks on end ok...my point is you do not draw that much all the time and your front amps draw very little compared to the subs, which are not constant either again unless your doing a sweep or Db Drag.

I know several vehicles that draw 110a. I am not going to argue. The original poster can decide what he wants to do. I believe 100% in alt>battery where draw is capable of exceding output.