Do I need a HO Alternator?

[>>SQL<< 10+ year member]

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.

Ok - you are right you did not offer the OP a battery.

I have read many of your posts, I can tell you are a smart guy.

So please explain how his system would work by just adding a second battery.

Op is wanting to run 2 amps

1) 400 watt

2) 1,00 watt

I will go ahead and say his amps will produce that power at 75% efficiency even though I feel 60% would be a more accurate number.

1,500 watts / 12 volts / .75 = 166.66 amps of current draw.

He has an 80 amp alternator

Using a/c , lights, ignition system draws apx 40 - 50 amps

This leaves 30-40 amps to charge the batteries.

lets say OP is on the highway enjoying his system at 75% volume.

166.66 amps (needed current for 100% volume * .75 = 125 amps of current draw

The system will draw the 30 - 40 amps of power that the alternator has left and then start pulling 85 - 95 amps from the battery.

How long can the OP drive like that?

How long will the batteries last being runs down then charged back up?

Wouldn't a 200 amp alt solve all the OP's issues and not require a $200+ second battery (plus wire and connectors)

Plus unlike a battery, the HO alt would provide 13.5 volts which is better for his electrical?

If somehow I am wrong with this simple math (and over 20 years of experience) please explain it to me.

This board is so full of repeated miss-knowledge that it is beyond sickening.

If your system draws more power than your alternator provides all you are doing is running down your expensive, heavy, and dangerous batteries.

You will need to charge them often and that makes no sense to me.

Just run an alternator capable of producing the amperage you need for your current needs.

Please correct me if I am wrong.

 

[sjv13 10+ year member]

[quote name='>>SQL

I have read many of your posts' date=' I can tell you are a smart guy.

So please explain how his system would work by just adding a second battery.

Op is wanting to run 2 amps

1) 400 watt

2) 1,00 watt

I will go ahead and say his amps will produce that power at 75% efficiency even though I feel 60% would be a more accurate number.

1,500 watts / 12 volts / .75 = 166.66 amps of current draw.

He has an 80 amp alternator

Please correct me if I am wrong.[/quote']

Wouldnt you do 1500watt / 12 volts x 0.75 (instead of divide by .75)?

If you're finding 75% of 125 (which is 1500 / 12) then you want to multiply by 0.75

When you multiply 1500 x 0.75 you get 93.75 which is quite different from 166.67

 

[>>SQL<< 10+ year member]

Wouldnt you do 1500watt / 12 volts x 0.75 (instead of divide by .75)?
If you're finding 75% of 125 (which is 1500 / 12) then you want to multiply by 0.75

When you multiply 1500 x 0.75 you get 93.75 which is quite different from 166.67

Nope because I am solving for 75% efficiency

An amp that is 75% efficient converts 75% of the electricity going in into power going out.

So that amp would use 100 watts of power to make 75 watts of output.

That is why the OP needs 166 amps of power to produce 1,500 watts

 

[GHOSTOWLGRID 10+ year member]

But he is not using the maximum 1500 watts?

The CS130 105 amp is a standard design that I gave a few references to.

The Higher output CS130 Alternators do overheat kinda fast, and they do not las as long as the 105 Amp version, they just get to hot.

That is why I went to the CS144 140 Amp output Alternator. It cools better and is larger and it required some changing to fit.

It is also built with heavier components, and it is a lot easier to mod the CS144 to get over 250 amps output with kits and parts you can buy, just make sure you do it right.

If he is willing to do it, they sell 250 amp output CS144 alternators. But I'm thinking the standard CS144 140 amp output design should be sufficient.

His car with everything on uses around 80 amps max, maybe a little less. At 12 volts, that is a max of 960 watts, (if I am correct).

Given 12 volts ideal output:

Now lets get the 105 amp CS130 alternator: you can get 1260 watts, which is an extra 300 watts.

Lets look at the 140 Amp CS144 Alternator: you can get 1680 watts, which is an extra 720 watts.

Now the alternator output goes higher than 12 volts, which yields higher wattage than I show. Which means he should be able to get by with a CS130 alternator that outputs 105 Amps.

However, I recommend he goes and buys a CS144 alternator that is close to his car mountings, then make some mods and install it and make it work correctly.

See with cars like the Toyota, they cut corners, they give you just enough to make the car work. This is why the alternator is only 80 Amps. You can not really add anything without installing a larger alternator.

Another issue to consider is space, is there space enough to install the CS144 alternator?

Maybe he should go with the CS130 as a start, he can always put it up for sale on ebay if he chooses the CS144 later on; because there are people who need them still. And it will be easier to install the CS130, less to change...

 

[gckless 5,000+ posts]

Math was explained above. If you plan on pushing the amplifiers, your alternator needs to be upgraded. However, if you don't listen at high volumes or at high volumes for only short periods of time, you would probably be fine with a battery. However, since the alternator is just as much or only a bit more, my recommendation is to do it right the first time. Get the alt. You will probably want a bigger system soon anyway //content.invisioncic.com/y282845/emoticons/nerd.gif.c6fa51ddf7ff75f1c0371fbc648f70ae.gif

 

[maltaudio 10+ year member]

Thanks for the replies guys. Appeciated.

Judging on the replies, it seems the best way to go would be to upgrade to a HO alternator.

Ghostowlgrid, the GM alternators you mentioned are not available where I live. I live in Malta (Europe), where GM trucks are not common. Also im not sure modifying alternators for the use of car audio is common practice, so much so that if I were to upgrade to an HO alternator, its safe to say I may be the only person on the island who has done such a thing since the majority of people who are into their car audio here use a capacitor to overcome any lack of alternator power.

I did get a quick quote from a US HO alternator supplier and was quoted just under $500 for the alternator and shipping to Malta. Im thinking this may be the best route to go since I have yet to come across a European HO alternator supplier, which would be preferential as I wouldent have to pay import duty.

 

[GHOSTOWLGRID 10+ year member]

Thanks for the replies guys. Appeciated.
Judging on the replies, it seems the best way to go would be to upgrade to a HO alternator.

Ghostowlgrid, the GM alternators you mentioned are not available where I live. I live in Malta (Europe), where GM trucks are not common. Also im not sure modifying alternators for the use of car audio is common practice, so much so that if I were to upgrade to an HO alternator, its safe to say I may be the only person on the island who has done such a thing since the majority of people who are into their car audio here use a capacitor to overcome any lack of alternator power.

I did get a quick quote from a US HO alternator supplier and was quoted just under $500 for the alternator and shipping to Malta. Im thinking this may be the best route to go since I have yet to come across a European HO alternator supplier, which would be preferential as I wouldent have to pay import duty.

If I am correct, they will be under different part numbers and different division listings, because the GM europe division is different.

What about ebay? You might be able to get away with buying one on ebay with paypal?

The CS130 and CS144 were only examples, you have to search around at different auto makers and different alternator designs they have for the different engines...

Good luck with your modifications, I will try to help if I can in the future and if I see your threads.

Like he said above, you might be able to get away with a second battery but still, once it discharges enough, it becomes somewhat useless. So yah. That converstion came and ended, so I won't bring it up again.

Unfortunately for me, I do not know what exists in Europe as I live in the USA, so... Good luck, I can't really look to much to try to help you find one. But I can try to help with schematics and the like if I have part numbers and specs, etc...

 

[gckless 5,000+ posts]

There are a bunch of good alternator companies. I personally have a DC Power Inc., there are also Mechman, Iraggi, Ohio Generator, and a couple others that aren't coming to mind right now. Search around on this site, you'll get some opinions, and you can also go on their websites and see what they offer. If they don't have one for your vehicle, email them for a quote.

 

[sjv13 10+ year member]

[quote name='>>SQL

An amp that is 75% efficient converts 75% of the electricity going in into power going out.

So that amp would use 100 watts of power to make 75 watts of output.

That is why the OP needs 166 amps of power to produce 1' date='500 watts[/quote']

Ah, I see what you mean. I was assuming the amps were over 100% efficient if my way worked haha

 

[GHOSTOWLGRID 10+ year member]

There are a bunch of good alternator companies. I personally have a DC Power Inc., there are also Mechman, Iraggi, Ohio Generator, and a couple others that aren't coming to mind right now. Search around on this site, you'll get some opinions, and you can also go on their websites and see what they offer. If they don't have one for your vehicle, email them for a quote.

^ THIS! This is helpful to the OP! //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Like I said, your not limited to a GM alternator or a custom HO alternator. There are options! //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Ah, I see what you mean. I was assuming the amps were over 100% efficient if my way worked haha

Something along those lines. But the amps are better than that.

But then again, that is hard to measure, And that is at max output nonstop.

Read below my reply to what you replied.

[quote name='>>SQL

An amp that is 75% efficient converts 75% of the electricity going in into power going out.

So that amp would use 100 watts of power to make 75 watts of output.

That is why the OP needs 166 amps of power to produce 1' date='500 watts[/quote']

I just realized your math is wrong. lol

1500 watts divided by 12 volts is: about 125 amps.

1500 watts divided by 13.5 volts is: about 111 amps.

Cars run around 13 volts...

My Car with everything being used, I have:

1) Lights: 500 watts.

2) The power consumption of everything else on my car before mods: 850 watts.

3) The power consumption of my head unit and amp, lets round up for fun: 150 watts.

This gives me a grand total of about 1500 watts consumed.

Now lets pretend my car only runs at 12 volts, The current draw will be something like: 125 amps.

Now lets being the reality of what my car runs at all the time,, 13.5 volts average, now my current is: about 111 amps.

(This is why my 105 amp alternator was just not enough, all I needed was a little extra, but I picked the 140 amp supply because it was the next size up).

The OP's vehicle at stock consumes a max of 80 amps max at about 13-13.5 volts. Lets say 13 to make it easy.

Lets say his amp draws 100 watts. Well, you will draw about 8.3 amps at 12 volts, and about 7.6 amps at 13 volts.

The 105 amp alternator would be more than enough also considering that is max power consumed from the amp at max operating load.

Now, lets assume a combination of audio amps pulls a max of 30 amps: 80+30=110 amps draw total.

Lets assume a combination of audio amps pulls a max of 60 amps: 80+60=140 amps draw total.

But, the power pulled will never be at a constant max, it will always be variable and based upon the volume knob in the car.

Given this, the OP can be able to better select an alternator.

BUT, Given math like this, there is, its considered the ideal situation, the real world application will be more or leess given tolerances and watever.

So with that, I suggest the OP pick something to allow a little extra.

Because given audio systems, you will always want to upgrade and increase power later, I know I did. lol