100amp alt with EFI, fan, water pump...

Discussion in 'High Tech Retrofits' started by woody80z28, Oct 11, 2014.

  1. flak monkey

    flak monkey Veteran Member Lifetime Gold Member

    Messages:
    1,064
    Likes Received:
    4
    Joined:
    Aug 5, 2011
    Location:
    Norfolk, UK
    EFI, electric gauges, fan etc all running on a 63 amp here - no problem at all.

    Gauges will only draw 1-2 amps max. EFI itself including injectors will be <5 amps, fuel pump max 10 amps, but under normal load they pull <6 amps continuous.

    You aren't adding much extra load with EFI in reality.

    Most modern cars with ABS, EFI, Stability control, Heated front and rear screens, heated seats, AC etc will have a 110amp alternator at best.

    Your current 100A alt will be just fine.
     
  2. Todd80Z28

    Todd80Z28 Moderator Staff Member Lifetime Gold Member

    Messages:
    11,850
    Likes Received:
    421
    Joined:
    Jun 11, 2002
    Location:
    Northern VA
    No. The alternator supplies a constant, regulated voltage. The amp output on the box is the rated output- i.e. how much sustained current it can handle without dropping voltage and/or overheating.

    FWIW, my 2006 Acura TL that has all sort of electrical gadgetry uses a 130A alternator. I think you should be fine. HOWEVER, you will be testing the limits of the V-belt at 100amps, should the system need that (e.g. lower RPM, start with low-ish battery charge state).
     
  3. mrvedit

    mrvedit Veteran Member

    Messages:
    1,356
    Likes Received:
    4
    Joined:
    Jun 12, 2009
    Location:
    Ann Arbor, MI
    Sorry to be an anal guy, but I'm pretty sure your electric water pump takes more than 5 amps:

    "The pumps from Meziere and Moroso all draw from eight to 12 amps under continuous use, while possibly spiking a few amps higher at initial start up, which is the case with many electric motors."

    From an informative article about water pumps:
    http://www.lsxtv.com/tech-stories/f...t-you-should-know-about-electric-water-pumps/

    Again, sorry to be anal about such details. It really doesn't matter either, because as everyone is saying, 100 amps should be plenty for the OP.
     
  4. woody80z28

    woody80z28 Veteran Member Lifetime Gold Member

    Messages:
    5,601
    Likes Received:
    77
    Joined:
    Sep 8, 2004
    Location:
    walton, ny usa
    Mine's a Proform. I was sure it was a 5A fuse, but remembered once I saw the specs it's a fusible link, but listed as 5A draw (only 35gpm compared to 55 for the Meziere I saw). But I'm sure it does draw more on initial start.
    http://www.summitracing.com/parts/pro-66225bk/overview/

    Todd I don't forsee any issues with the V-belt, but I'll find out pretty quick. haha I have a custom-fabbed low-mount bracket with precise adjustability for the tension.
    [​IMG]
     
  5. DFWJ

    DFWJ Veteran Member

    Messages:
    300
    Likes Received:
    0
    Joined:
    Aug 16, 2012
    Location:
    DFW
    100 Amp Alt should be enough with a single electric fan. The fan, fuel pump, and lights are going to take the most juice.

    I used to run a 63Amp and it wouldn't hold 12v when my dual electric fans kicked on.

    I now run a Powermaster 150 amp. and with an underdrive crank pulley it idles at 900rpm at 14.4V, when the fans kick on voltage drops to 13.8V...

    Running FAST EFI, MSD Digital 6AL, Spal dual fans, Holley Dominator Fuel Pump.
     
  6. spav350

    spav350 Veteran Member Lifetime Gold Member

    Messages:
    601
    Likes Received:
    0
    Joined:
    Apr 8, 2009
    Location:
    Corpus Christi, Tx
    You should be fine. I'm running all that you described except the electric water pump and my system runs great.
     

Share This Page