more power output
A turbo. Or you could try putting in a supercharged 3800, but I don't know if that is easy or not to do. The Grand Am's usually get the 3.4L and I don't know what would be involved.
A good place to start is a Cold Air Intake and a bigger exhaust, not just a fart can. Then move to higher performance plugs and wires. I would consult a grand am/alero forum for modding beyond that.
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