make it breathe better. high flow cold air intake and a bigger exhaust and maybe even a 4-2-1 header and bigger throttle body. it'll sound like a weed wacker, but you wont have any restriction in the exhaust or intake. get your ECM reprogrammed. bigger cams. of course nitrous. underdrive pulleys. most of these upgrades wont be noticeable by themselves but if you get them all done at the same time you will notice a big difference. especially if you put nitrous on it.