02 Stock Alternator Amps?

Discussion in 'SN95 4.6L Mustang Tech' started by di0de, Feb 22, 2004.


  1. di0de

    di0de Founding Member

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    I was just wondering how many amps the 02 alt was rated? I have a RF 500a2 amp with 2 12w3's and have some dimming issues when the volume is high and only during bass notes. Since I'm adding another 350a2 (100wx2 rms) I'm thinking I might need another alt instead of bothering with a cap..
  2. 8yourZ06

    8yourZ06 New Member

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    I used to be into the audio thing so I know what your saying.
    The stock alternator is rated at 130 amps. I would probably suggest a 200 amp alternator.
  3. jammin7998

    jammin7998 New Member

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  4. gaerisch

    gaerisch New Member

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    Get a good alternator from PA Performance. These are all new ( only the housing is rebuilt) I have a 175 amp unit from them with the heavy gauge wire kit ( recommended). I have not had any problems since. My factory alternator started going just after the warranty on the car expired.
  5. restomod66

    restomod66 Member

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    200 amp alternator and an Optima battery, never have to worry about it again. The stock alternator wasn't designed with the demands of a big audio system in mind, especially multiple subs/powerful amps. I used PA Performance when I upgraded the alternator on my 66 Mustang to a modern 3G unit and was very happy with it.
  6. trinity_gt

    trinity_gt Advanced Member

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    I doubt a "big" alternator will fix your dimming issues.

    There'll still be too much output resistance in the alternator and too much time lag in its load regulation for it to be effective against large transient loads like bass hits.

    There's also too much resistance and inductance in the wiring, even low-AWG stuff.

    You need to store energy in a very low-impedance source at the point of the load (i.e. a low ESR capacitor.) It's the same principle PCB designers use when they put bypass capacitors at the power pins of power-hungry processors: it helps reduce the effects of inductance on the board and in the power supply wiring and ensures the processor gets decently clean power as transient demands vary.

    In addition to low-ESR caps a second, auxiliary battery, placed very near the point of load makes a good low-impedance source for stuff like amps. It can be charged by the car's alternator through the use of a marine battery isolator.

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