alt. upgrade...

Discussion in 'Technical' started by 71gold, Sep 16, 2018.

  1. 71gold

    71gold Frank Cooper Supporting Member

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    after installing my new E-waterpump I thought it time to bump up the juicer.
    I have...
    E-fan (Volvo)
    E-waterpump
    A/C
    MSD Atomic EFI
    MSD timing controller
    E-fuel pump
    fog lights
    running lights
    wipers
    sequential tail lights (6 1157 bulbs)

    with all this I had the alt bumped up from 103 amps to 200 amps ($169)
    before on startup I would have 14.3V. as it warmed up it would drop to 13.1V. if I turned the A/C on it dropped to 12.5V. if I set at a stoplight at idle more than a few sec. it would drop lower (11.9V).

    now...startup is 14.5V...
    with all this on:

    E-fan (Volvo)
    E-waterpump
    A/C
    MSD Atomic EFI
    MSD timing controller
    E-fuel pump
    fog lights
    running lights
    wipers
    sequential tail lights (6 1157 bulbs)

    it stays @14.3-14.5Vs anything above 800RPMs...anything below 800RPMs it's 12.3-12.5Vs...

    also with the install of the E-waterpump and a new alt bracket I could do away with the long serpentine belt, idlers and belt tensioner...:thumbs2:
     

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  2. bmcdaniel

    bmcdaniel Senile Member Supporting Member

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    Try finding a smaller diameter alternator pulley to speed it up.
     
  3. stumanchu

    stumanchu Stuart

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    Well, sounds like a good turn of events.....24K is quite the electric post too.
     
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  4. 71gold

    71gold Frank Cooper Supporting Member

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    if I can keep it at 12.3-12.5V at idle that would be OK. I'm looking for a...clutch pulley...if it's a smaller OD that would be a plus. have entertained the idea of putting a one way bearing in a stock or smaller pulley...:yup:
     
  5. bmcdaniel

    bmcdaniel Senile Member Supporting Member

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    12.3-12.5V means your battery is discharging. Hope you don't sit idling too long.
     
  6. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    I would run the setup for a while. Don't think you will/rarely operate all those electric devices at once. Don't think you will op below 800 rpm a lot. I run 130amp w/ AC, elec fan and stero amp at idle about 13.8 according to Auto Meter gauge. I have car setup to run 800 rpm at idle.
     
  7. bmcdaniel

    bmcdaniel Senile Member Supporting Member

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    Hot summer night, raining, sitting at a stop light with your foot on the brake...
     
  8. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    I have been in situation , hot summer nite, stop light, AC , stero amp, never had an issue for a few minutes at the light. If I run into a problem for long wait on something like train crossing, can turn off head-lights "use park lights" and put car in neutral.
     
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  9. Krazy Comet

    Krazy Comet Tom

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    Possibly but that's near normal battery voltage, drain would be small.
     
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  10. 71gold

    71gold Frank Cooper Supporting Member

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    "Resting fully charged 12 volt batteries are around 12.8-12.9 volts, and flat dead ones are at 12.0 volts, so 12.4 volts on a resting battery means it's about 50% charged."
     
  11. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    I believe 12.5 is normal rest voltage and would/could be far greater than 50%! IIRC I have checked voltage on my 7 yr old wet cell and at rest it's around 12v or so, never had an issue w/ it powering all accessories or cranking engine. I keep batt. on maintainer during long inactive periods; not going to push my luck, getting new one next season.
     
  12. Krazy Comet

    Krazy Comet Tom

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    You cannot use static voltage to determine how much charge there is in a battery. A rough guess at best, BUT a battery with 12.8 12.9v is overcharged.

    Seen batteries with 12.6v not begin to crank the engine, yet another with just barely 12v cranks fine.
     
  13. 71gold

    71gold Frank Cooper Supporting Member

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    volts but no cranking amps.
     
  14. 71gold

    71gold Frank Cooper Supporting Member

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    got this from a Google search...

    "Resting fully charged 12 volt batteries are around 12.8-12.9 volts, and flat dead ones are at 12.0 volts, so 12.4 volts on a resting battery means it's about 50% charged."
     
  15. Krazy Comet

    Krazy Comet Tom

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    But in real world if battery had no cranking amps, it would NOT be turning starter.
     

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