No offense but you have one of the worst year models for the GT. That single overhead cam 4.6 is a dog for that year model. Best thing to do is to get a set off 99 GT heads and cams youll see big horsepower gains. If you dont want to get that serious get a gear preferrably 3:73. A gear will wake that car right up. Then basic bolt ons h-pipe flowmasters mass air etc....

Jomar