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Loss of MPG with aftermarket systems

Discussion in 'Prius c Audio and Electronics' started by mothandras, May 25, 2012.

  1. mothandras

    mothandras Junior Member

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    Vehicle:
    2012 Prius c
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    Two
    Anyone else experiencing a dramatic loss in MPG with an aftermarket system?

    I installed new headunit/replaced all mids/ XD700/5 watt 5 channel Class D JL NEXD amp/ 10" sub.

    Haven't done the math exactly but it looks like about a 10MPG loss for me.

    10MPG is huge.. not sure why its so much.
     
  2. F8L

    F8L Protecting Habitat & AG Lands

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    It's not really possible unless you added 1,000lbs worth of equipment and run 5,000w. LOL

    More likely you are suffering from something else like weather, change in commute, tire pressure or simply not having nailed down an accurate baseline mpg. If you are new to the Prius world it can take awhile to learn what environmental conditions and driving techniques can do to mpg. I used to run 1,900w (RMS) and 2 12" subs in a box that weight 95lbs yet I never could determine a mpg difference. Unless the c is drastically different than the GenII then I doubt you are losing 10mpg from the stereo. The easy way to test this idea is to run the system for the next few tanks while tracking weather conditions, driving speeds, AC use etc.. Then take the fuse out of the large amp and remove the subwoofer box and drive around for a few more tanks. That is what I did to come to my conclusion. :)
     
  3. Daze

    Daze Prius C Owner

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    I installed an Alpine Type R 10" subwoofer with the Alpine MRP-M500 amp (500 watt) in my C and have not noticed any MPG drop at all.
     
  4. actiondonkey

    actiondonkey Member

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    I haven't seen any noticeable drop in mpg. Is your amp hooked up to the EV battery instead of the 12v battery?
     
  5. ftl

    ftl Explicator

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    That would definitely turn the volume up to 11!
     
    dellrio likes this.
  6. mothandras

    mothandras Junior Member

    Joined:
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    Location:
    Lexington, KY
    Vehicle:
    2012 Prius c
    Model:
    Two
    Since this car doesn't have an alternator, I am assuming the regular 12V battery gets recharged through the wheel braking too? If I plan to add more equipment to the car, like an xbox 360 would I benefit from a heavier duty battery? Looks like I will have to install a pretty good size invertor and hook it straight up to the 12V battery.