It would bounce so much.. Lets just say it would put the "horse" in horsepower.
You don't wanna lower your car 3 inches unless you're willing to spend money on tires every 3 months, or you're willing to spend lots of money on suspension work in order NOT to wear out your tires that quick.
2 inches would do just fine, and you wouldn't need much work done to your suspension other than a good wheel alignment. Its not worth the trouble to go any lower, ride is shitty. 2 inches or less is probably the biggest drop you can get for your car anyways.