The old pads could have been glazed and therefore not gripping. Previous owner could have been to hard on them at break-in. If you didn't sand or turn the rotors when you put in the new pads they could do the same thing again or at least take a long time to seat.
96LXV6 heavily un-modded due to family addition.
87Renault GTA convertible, chopped springs, Ford Premium Sound, but otherwise stock.
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