HO Alternator Question

[do9105]

I have a question about getting a high output alternator. At what point is it necessary to have one? In specifics.. I'm wondering how many watts RMS will it take until the stock bonneville's alternator wont be able to keep up? (105 amps?)

'03 Bonneville SE

[00Beast]

Better question for you, what do you plan on adding?

[do9105]

Amp - http://www.woofersetc.com/p6856/FD-2200 ... lifier.htm
Amp - http://www.woofersetc.com/p6859/FD-6001 ... lifier.htm

That's it for now. How do you think the stock alternator would do with those two amps?

[tan96ssei]

you should be fine with the stock. if the lights flicker with those amps then i would just get a 140 amp alt. from a SSEI

[do9105]

do you know if for sure a ssei alternator would fit on my 03 SE? Also, could I just give my alternator to a shop and have them upgrade it?

[01bonneSC]

do you know if for sure a ssei alternator would fit on my 03 SE? Also, could I just give my alternator to a shop and have them upgrade it?

an 03 SSEi alternator should fit, but yes if you can have your car out of commision for a day an alt/starter shop should be able to upgrade to your need and would be cheaper than buying a rebuilt SSEi one. We have a really good shop in DeKalb, IL called Mars, really quick turn around.

[do9105]

well... I jumped to gun thinking that my old alternator was broken and so I bought a new one. Mistake! haha. But if I do get it rebuilt my car won't ever have to go out of commission.. Either way it didn't fix my voltage going up and down between 14 and 16. Do you know what the prices for a rebuilt alt would be? I'm looking to get 150 amps or more if I get it rebuilt. Either way I'm gonna wait until I actually have my amp and sub installed before I get a HO alternator or a rebuilt one.

[tan96ssei]

Either way it didn't fix my voltage going up and down between 14 and 16.

honestly the amperage output on the alternator is not going to increase your voltage. once you install the full system in the car you will notice the voltmeter bounce from 14-16 down to 10.5-12... this is all variable as to the size of your amps the amperage they pull and the size of the inline fuse you have (the amperage you are allowing to go from battery to amplifier)

for your stock stereo system doesn't affect your voltmeter and the voltmeter consistently reads 14-16 volts. now you have a full sound system new head unit, four channel amplifier (400 watt amp for this example), and a 1000 watt amplifier to power your subs. so on average most amplifier pull 40 amps so you have two amplifiers equalling 1400 watts of power, and 80 amps needed to push the amplifiers. this means when your stereo is going you are pulling 80 amps from the battery at any moment. now as you are driving you dont notice the lights flicker cause your RPMs are high enough that you are using the alternator to replenish the voltage loss. but at idle say at a stop light you notice the lights flicker and get dim. this is because at idle you are not really getting any thing from the alternator at least not enough to compensate for the 80 raw amps you are pulling to run your sound system. that is why most sound system competitors add a capactitor, a second battery with a battery isolator or a second alternator or a HO alternator.

so you got a few options two are a little less fesible and more expensive. the cheapest and easiest fix is a capacitor rated to handle the total amperage and wattage your system needs, or getting a beefier HO alternator. the not so cheap and not so easy fix unless your in a diesel truck is a second battery or a second alternator.

[do9105]

i realize that once i get my 2nd amp my voltage is gonna drop considerably. Are you by any change Mars? from the shop that 01bonneSC was talking about?

do you know if for sure a ssei alternator would fit on my 03 SE? Also, could I just give my alternator to a shop and have them upgrade it?

an 03 SSEi alternator should fit, but yes if you can have your car out of commision for a day an alt/starter shop should be able to upgrade to your need and would be cheaper than buying a rebuilt SSEi one. We have a really good shop in DeKalb, IL called Mars, really quick turn around.

seeing as you are from DeKalb, IL and he referred me to a shop in IL... lol. If you are from the shop that he was talking about, what would the price be on getting my alternator rebuilt so it puts out a higher amperage?

[tan96ssei]

yes i know of mars here in dekalb but no i am not from there. 815-756-9019 is the number i found for mars give them a call and ask for prices cause honestly i dont know how much it costs.

[01bonneSC]

I think a stadard rebuild is only $35. Then if you want more stuff done to it, obviously itll go up a bit, but very much less than buying new/rebuilt from the store.

[88bonnsse]

you dont want a rebuilt alyernator for $45..

you will want to go to a junk yard or even ebay and buy a used 140 amp ssei alternator if you cant afford to spend the $200 plus for a ho alt.. either way you will still be fine with the 140 amp alt from the ssei..

if your lights still dim then add a 2-3 farad capacitor..


i have a high out put alt from iraggi alternators and its 260 amps.. i am running 3 batteries and i still drop down to 12 volts.. its normal unless you have like 10 or more batteries on only about 3-4 amps..



and what do you mean 16 volts.. no way you are getting 16 volts unless you have upgraded your electrical system and bought special 16 volt batteries with a custom alt that will kick out 16 volts to charge your 16v batteries..

that cost alot of money.. lol.. too much money..


so yeah look into the 140 amp alt and a good cap if needed.

[Bugsi]

I'm looking to get 150 amps or more if I get it rebuilt.

If that's the case, I'd just get an SSEi alternator from a junk yard or on eBay.

If your system is seriously measuring 14 to 16 volts, something is seriously wrong and you're probably cooking your battery. Since you changed alternators and the reading didn't change, your gauge is probably off. Try measuring with a DVM.

Incidentally, having a 150-amp alternator, or a 260-amp alternator doesn't mean it will be steadily pumping that much current into your battery. All it means is that it has the capability to do so. I have serious doubts that your vehicle's electrical system, even with both of those amps running, would ever draw that much current.

If you just like to spend money, then the sky is the limit, buy the biggest, most expensive, highest output alternator you can fit under the hood.
If you want a reliable alternator that can meet all your needs at a reasonable price, get a stock SSEi alternator.

Check your RPO codes, you may have one already. My SE came with the 140 amp alternator.

[99bonnieSE]

also, i do believe you can get away with a big 3 upgrade, if you're not sure, let me know, i can help ya out. that is NOT much power at all. the biggest thing hurting you is the stock main power wires going from the alt to the batt, the motor to the batt, and the body to the batt.