How many watts can a 160amp alt take?

[ssracerx2 10+ year member]

Right now I have a 105 amp alt. and I am lacking power, how many watts will a 160amp alt handle? Right now I am running about 1400watts with my mac and arc amps. Thanks

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[ws140 10+ year member]

depends on efficency. 1500watts rms.

 

[n2audio 5,000+ posts]

what do you mean by lacking power?

Dimming lights does not constitute lacking power - it means you have a high demand audio system.

If your car begins to turn over slowly when you try to start it - THEN your electrical system isn't cutting it.

With a 105 amp alt and a good battery a 1500 rms system shouldn't be a struggle at all.

With a 160A - I think 3kw would be a reasonable expectation.

Here's a pretty good read on current demands of car audio:

The Quote:

--------its very possible that your alt ernator will do just fine powering that 3000 watt system as long as there are not a lot of other loads on the [electrical system] ------------here is how it works out------a 3000 watt system driven to FULL power with music will have a peak to average ratio of at least 10 db unless it is driven into gross distortion all the time-------this means the long term power output will not exceed 300 watts-------factor in an efficiency of 50% and that leaves you at 600 watts of continuous electrical consumption-------and thats if you don't have pauses between song tracks or between different CD's--------and also considering that you NEVER turn the volume down at all------the system you describe will use a little more than half your 70 amp alternators capacity as long as the engine is running............RC

The link:

http://www.carsound.com/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic;f=1;t=020650

 

[ssracerx2 10+ year member]

what do you mean by lacking power? Dimming lights does not constitute lacking power - it means you have a high demand audio system.

If your car begins to turn over slowly when you try to start it - THEN your electrical system isn't cutting it.

With a 105 amp alt and a good battery a 1500 rms system shouldn't be a struggle at all.

With a 160A - I think 3kw would be a reasonable expectation.

Here's a pretty good read on current demands of car audio:

The Quote:

--------its very possible that your alt ernator will do just fine powering that 3000 watt system as long as there are not a lot of other loads on the [electrical system] ------------here is how it works out------a 3000 watt system driven to FULL power with music will have a peak to average ratio of at least 10 db unless it is driven into gross distortion all the time-------this means the long term power output will not exceed 300 watts-------factor in an efficiency of 50% and that leaves you at 600 watts of continuous electrical consumption-------and thats if you don't have pauses between song tracks or between different CD's--------and also considering that you NEVER turn the volume down at all------the system you describe will use a little more than half your 70 amp alternators capacity as long as the engine is running............RC

The link:

http://www.carsound.com/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic;f=1;t=020650

The car also has a supercharger as well, I don't know if that matters or not, but the drain on the battery is to the point were the bass losses all of its punch, there is just not enough power to hit the bass notes at high volume. The voltage meter drops by 2 or 3 volts at each bass hit and other cars can actualy see my lights dimming like they are going on and off...

 

[n2audio 5,000+ posts]

Hmm, well, the obvious power problems you're describing leads me to think there's a problem in the wiring. I'm fairly sure the SC won't directly influence current consumption - it's just driven by the crankshaft. If I were you I'd trace the current path from battery(+) to amp to ground and hope there's something going on.

Is it possible your battery is getting old? Does your car start ok when you turn the key? Slow to turn over?

 

[ssracerx2 10+ year member]

Hmm, well, the obvious power problems you're describing leads me to think there's a problem in the wiring. I'm fairly sure the SC won't directly influence current consumption - it's just driven by the crankshaft. If I were you I'd trace the current path from battery(+) to amp to ground and hope there's something going on.
Is it possible your battery is getting old? Does your car start ok when you turn the key? Slow to turn over?

i know its not the battery because I switched it out to a new Optima Yellow top and it made no difference at all. I was a little suprized by that, I thought the battery would help a little. The car starts right away every time. Thanks for the help let me know if the new info makes any sence at all.

 

[namster44 10+ year member]

well those amps, mac and arc like current, as do many high end amps...they like current, give them more I say!

 

[joshpoints 10+ year member]

I'm not an electrical engineer and don't know that much, but out of all honesty that quote doesn't make sense to me.

A system that is rated at 3000watts rms when played loud is going to draw 300 watts. Now just because an amp isn't totally efficient doesn't mean that it doesn't draw the electricity, it just means that an amp wastes some of the electricity due to resistance and so on. The wasted power is turned into heat. Something that must be realized is just like audio equipment some alternators are overrated. Some of them may say that they produce 105 amps, but realistically they produce no where near this amount during typical driving. Some companies may rate an alternator at 105 amps, yet the alternator only produces this peak amperage at 5-6k rpm. This means in everyday driving you are getting no where near 105 amps. THis could be part of your problem. Before buying an after market alternator find out at what rpm this rating was found at. IT's just like that amp thing. A company builds a trashy amp that is able to peak at 1000 watts for a second, but can't produce a respectable rms wattage. If this was already stated sorry, but I was too lazy to read through the other posts.

 

[n2audio 5,000+ posts]

Guys, I'm assuming you know who RC is - his 10% duty cycle estimate might just be an estimate, but I tend to take his word, and I'm confident it's in the ballpark.

I only posted it to make the point that 160A or 90A - there shouldn't be any problems powering a 1400 watt system. Something else needs attention here. The overrated alt sounds reasonable to me.

 

[n2audio 5,000+ posts]

He said 3kw consumes roughly 35A on an average basis.

With 1400 watts -- IF you have system booming, headlights, foglights?, a/c blower, electric cooling fans - all running - you might begin to max out a standard sized alternator. And the system is probably the smallest draw.

Do an experiment -- Start your car - check voltage at idle - turn accessories on 1 by one. You should see that of the accessories the stereo will probably effect the voltage the least. In my case I get almost no voltage drop with the stereo playing at 3/4 volume (1000 rms), and almost a full volt when I turn on the a/c - 1/2V for lights, 1/2 volt for cooling fan.

That is why I find it hard to believe that simply the demand of the system is causing racer's problems. I think there's a cure w/o big electrical system upgrades.

 

[joshpoints 10+ year member]

Yeah, but you have an American car //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Those of us with Japanese cars are stuck with chincy-***, wimpy, overrated alternators that push shit for current at idle //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

Isn't that the truth.

 

[n0ftInc 10+ year member]

I was looking to upgrade mine.. Say I ran a system putting out about 5500wts.. What size alt. could I get away with and still have enough left for everyday occurances..?

 

[n2audio 5,000+ posts]

Yeah, but you have an American car //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Those of us with Japanese cars are stuck with chincy-***, wimpy, overrated alternators that push shit for current at idle //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

My car's 15 years old - 75A alt. - it might be more accurately rated, but 75's still pretty small - I do have an 850cca battery though.

 

[Rmsanger 10+ year member]

Sorry to jump into your thread but I was wondering about in estimate how big the alternator in a standard 2000 Civic EX would be. I actually have a model called a VP which is a cross between and EX and DX but I can't find the alernator ampage anywhere

 

[60_cent 10+ year member]

japanese cars do have some wimpy *** alt.

my caddy with a 4.9L V8 has a 140 amp alt stock.. :thumbs_up