2-3 grand will not get you a Turbo...maye the stafford Turbo when it becomes available.
2-3k worth of Performance mods w/out a supercharger or Turbo can include
cold air intrake or short ram Intake
exhaust
header
pulleys
nitrous
there are many other Performance mods though that are not technically 'performance' mods. these include weight savings mods such as
carbon fiber hood
lighter wheels
stickier tires among other things