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Need A Bigger Alternator

Discussion in 'The Garage' started by 87BrnRsd, Nov 10, 2004.

  1. 87BrnRsd

    87BrnRsd 1/2 ton status

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    I have the stock gm 87 alternator on my truck right now. When I turn my stereo up, the amplifier is demanding way too much power. The voltmeter sometimes drops below 10. The largest alternator I can find for my truck is only a 145 amper. What alternators that fit other makes or models will fit on my truck and offer in the 160-200 amp range? Thanks.
    BTW- Im semi-poor so the price needs to be under the $200 mark.
    -Harrison
     
  2. sublmnl1990

    sublmnl1990 1/2 ton status

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    There are a couple of sellers on ebay with either 180 or 200 amp, the alternator shop here will build you a 200 amp one life time warranty for a buck a amp. Thought it sounded cheaper that way. Nick /forums/images/graemlins/burb.gif
     
  3. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    I would be very suprised you would need something larger than a 145 amper.
     
  4. GMCLegacy

    GMCLegacy 1/2 ton status

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    a 200 amp alternator may sound like a solution, but you need to actually see what its output is at engine idle.

    i dont think a larger alternator is a fix-all
     
  5. TrcksR4ME

    TrcksR4ME 1/2 ton status

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    145 amp should be plenty as long as you get good output at idle. A good quality 200 amp alt. is gonna cost a lot more than $200 to buy new.
     
  6. 84_Chevy_K10

    84_Chevy_K10 Banned

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    A 200 amp alternator is about $350.
     
  7. surpip

    surpip 1 ton status

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  8. GMCLegacy

    GMCLegacy 1/2 ton status

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    classic ebay lingo

    "I am told it is 160 amp output"

    he doesnt know what he is even selling. its probably a 36 amp'er
     
  9. 79cheyenneblazer

    79cheyenneblazer Registered Member

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    when buying a bigger alternator be careful to get a good quality one, I put a 94 amp on my blazer with the DEKA 1000 battery because the stock 60 wasn't enough for my stereo, and the alternator regulator screwed up and kept charging the battery, until it finally fried that fusable link on the firewall, and in the process frying my cb radio and my factory tach, /forums/images/graemlins/angryfire.gif
     
  10. 85mudblazin

    85mudblazin 1/2 ton status

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    what king of amp are you running that it is dropping below 10 volts?? my amp has 800 watts and I have plenty of power all day long, maybe you are having charging problems. /forums/images/graemlins/dunno.gif
     
  11. 79cheyenneblazer

    79cheyenneblazer Registered Member

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    check your grounds, possibly run like a 4 gauge wire off the negative on the battery to the body, it sorta helped mine out when I did that cause I have the same problems
     
  12. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    [ QUOTE ]
    what king of amp are you running that it is dropping below 10 volts?? my amp has 800 watts and I have plenty of power all day long, maybe you are having charging problems. /forums/images/graemlins/dunno.gif

    [/ QUOTE ]
    Ditto, I'm running 1500 watts (probably more) and have huge dual 13.5" electric fans and with my stereo on about 1/3 power I can have everything on including the A/C. My 100 amper is just enough. My 100 amper can't keep up with my stereo either at full power, a 145amper probably couldn't either but at that level everything is so loud I can't see strait sitting in the driver seat anyway. My guess is if you are needing more than a 145 than you system is easely that loud and is way to much for actually driving. It's dangerous and annoying to other drivers to have the amps loud enough to need that much amperage. Not to mention you will be saying "huh" for the rest of your life at those kinds of levels for long.

    Get a 145 amper and keep the stereo down quiet enough to where you could here another vehicle's horn next to you and you won't have any charging issues. Having big amps and lots of boom is definantly fun with buddies and shows etc.. but be responsible and do yourself a favor and don't blast it while driving.
     
  13. spearchucker

    spearchucker 1/2 ton status

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    [ QUOTE ]
    Get a 145 amper and keep the stereo down quiet enough to where you could here another vehicle's horn next to you and you won't have any charging issues. Having big amps and lots of boom is definantly fun with buddies and shows etc.. but be responsible and do yourself a favor and don't blast it while driving.

    [/ QUOTE ]
    Please bring your soapbox to my neighborhood. /forums/images/graemlins/bow.gif
     
  14. jekbrown

    jekbrown I am CK5 Premium Member GMOTM Winner Author

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    dual batterys and caps might be a better solution than a larger alternator. As stated by others, many high amp alts dont really kick out that much more amperage when at idle.

    j
     
  15. 87BrnRsd

    87BrnRsd 1/2 ton status

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    I am running a soundstream tarantula 700/2 amp. I think its a 700 continuous watt amp but has a 1400 or 1600 watt peak. Im pretty sure all of my grounds are good because I just put the engine in last summer and I made sure everything was fine then. Part of the problem is my volts dropping below 10 and when the subs hit it actually drops the oil psi by about 5 psi. Another reason why I want a larger alt is because when I am listening to music at a loud but reasonable volume, if there is a song with quite a few bass notes in it, there isnt enough power for the amp and it will kick off for about 5 or so seconds and then kick back on. Its quite annoying in the middle of a song. I dont listen to rap so the amp isnt demanding THAT much power. Im saying its kicking out on Dave Matthews which definitely doesnt have much bass. Im kind of opposed to caps because they can actually worsen the problem if the cap gets drained. I also dont want to be shocked due to a cap when I try to work on my truck. Does anyone know what the stock alt on my truck puts out at idle? Could be I just need an alternator that will put out a bit more at idle. Thanks.
    -Harrison
     
  16. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    [ QUOTE ]
    soapbox

    [/ QUOTE ] I am not familiar with this word. /forums/images/graemlins/confused.gif
     
  17. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    First thing I would do is add a capaciter, I know you don't like them but that would definantly help solve your dipping to 10V's. It will help and smooth out the power requirement to your battery and alt. which really helps save your alt. and battery. What ohm load are you running? How is the amp wired? Your cutting out could be from the amp overheating or like you said, running out of power. I would imagine that with 1400 watts a 145 amper should be able to keep up fine. As far as what they put out at idle, I don't know but when I show my stereo to someone and we are sitting inside I just give the engine about 1000RPM's. /forums/images/graemlins/waytogo.gif
     
  18. firefighter184

    firefighter184 1/2 ton status

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    There was an article in one of this month's wheeling mags showcasing a 500 amp alternator for late model GMs!
     
  19. sickquad

    sickquad 1/2 ton status

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    [ QUOTE ]
    I am running a soundstream tarantula 700/2 amp. I think its a 700 continuous watt amp but has a 1400 or 1600 watt peak. Im pretty sure all of my grounds are good because I just put the engine in last summer and I made sure everything was fine then. Part of the problem is my volts dropping below 10 and when the subs hit it actually drops the oil psi by about 5 psi. Another reason why I want a larger alt is because when I am listening to music at a loud but reasonable volume, if there is a song with quite a few bass notes in it, there isnt enough power for the amp and it will kick off for about 5 or so seconds and then kick back on. Its quite annoying in the middle of a song. I dont listen to rap so the amp isnt demanding THAT much power. Im saying its kicking out on DAVE MATTHEWS which definitely doesnt have much bass. Im kind of opposed to caps because they can actually worsen the problem if the cap gets drained. I also dont want to be shocked due to a cap when I try to work on my truck. Does anyone know what the stock alt on my truck puts out at idle? Could be I just need an alternator that will put out a bit more at idle. Thanks.
    -Harrison

    [/ QUOTE ]

    Problem #1: You listen to Dave Matthews.
     
  20. firefighter184

    firefighter184 1/2 ton status

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    [ QUOTE ]
    [ QUOTE ]
    I am running a soundstream tarantula 700/2 amp. I think its a 700 continuous watt amp but has a 1400 or 1600 watt peak. Im pretty sure all of my grounds are good because I just put the engine in last summer and I made sure everything was fine then. Part of the problem is my volts dropping below 10 and when the subs hit it actually drops the oil psi by about 5 psi. Another reason why I want a larger alt is because when I am listening to music at a loud but reasonable volume, if there is a song with quite a few bass notes in it, there isnt enough power for the amp and it will kick off for about 5 or so seconds and then kick back on. Its quite annoying in the middle of a song. I dont listen to rap so the amp isnt demanding THAT much power. Im saying its kicking out on DAVE MATTHEWS which definitely doesnt have much bass. Im kind of opposed to caps because they can actually worsen the problem if the cap gets drained. I also dont want to be shocked due to a cap when I try to work on my truck. Does anyone know what the stock alt on my truck puts out at idle? Could be I just need an alternator that will put out a bit more at idle. Thanks.
    -Harrison

    [/ QUOTE ]

    Problem #1: You listen to Dave Matthews.

    [/ QUOTE ]

    Dave Matthews is an inspiration to peaceniks and environmentally conscious frat boys all over the world...
     

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