what could i do to my mustang performance wise?

Not sure about "cheap" but I'd suggest adding a chip to the engine. If you go to ebay and type in "1998 ford mustang gt chip" - you should see many merchants selling chips for that car. Other than that, I'd also suggest new rims and tires - always helps with the handling. good luck lstein

It not very cheap but a supercharger will be worth the money in horsepower increase. A cheaper solution is NOS but engine failure is common with these system. Search e-bay motors.

A good mandrel bent true dual exhaust with an x-pipe and a K&N FIPK Kit will give you the most bang for the buck. I like Flowmasters , but Magnaflows flow more freely supposedly.

And don't forget a set of 3:55 gears ...

with checkM8 - a nice set of gears i'd go with 3:73's. takes away from top end, but your take off will be nice, as high as 4:11's even... along with gearing you could just get the typical - Cold air intake, exhaust, and definately look into a programmer for it... if you want to get wild, drop a cam in there - cost upwards of $1500 - $1800 but could very well give you that power you're looking for. CAI and exhaust wouldn't come close to the power increase of the cam... there's some suggestions.

Cold air intake is always a good choice, as well as the engine chip that was mentioned above. Another thing that you can do is always put a turbo or super charger in it depends if you want more acceleration or top speed.

Remove 4.6, drop in Coyote 5L :) Id say forced induction gives ya the best bang for the buck. Or some 3.73 gears.

no such thing as 'cheap horsepower' now adays, best bang for the buck would be a blower with nitrous

if your going to go cams get atleast the PI heads from the 99-04 gt and get a typhoon and get the matching intake manifold or if you have a little extra cash get the trick flow intake then do CAI and full exhaust. that should put you over 300+ whp