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underdrive pulleys stock

  1. 5.0L Talk
    I currently have a serpentine underdrive pulley on my mustang and, for a daily driver, I hate it. It really inhibits the charging system and every time I turn my lights on, my battery drops to around 9 volts. I dont have a big stereo or anything and just bought a new 800cca 1000ca Optima Redtop...