l know about turbos and superchargers but l think thats excessive.

cold air intake and performance exhaust. cheapest way but dont expect much hp

Which engine? 3.0L Vulcan or 3.0L Duratec? Vulvan = supercharger, Duratec = performance exhaust. That is all you can do. Intake will gain you 2 HP, woo. You can get a computer tuner for either, l am sure.

Basic bolt ons will give you a little horsepower and are very affordable for the novice. Intake, headers, and exhaust.

Sell it and buy a better performer.

Do not bother, these cars have the worst transmission ever built in them & adding power to the engine will only wear it out quicker. If the car is stock & driven nicely & well looked after the tranny will usually last about 120k miles but if u add a super charger it will probably last about a week if u r lucky & trust me they r not cheap to replace. These cars r junk & that could be why Ford has a class action law suit against them for the defective transmission that they installed in every Taurus & Sable ever built. The transmission is not the only problem with these cars either they r a nightmare to own (trust me l know first hand) Seriously get a better car, think about a Crown Vic or a Mustang.