"Narrator: I am Jack'* complete lack of surprise. "
As with all engines make it breath better so to speak. cram more air and fuel in and let it get out easier in laymens terms.
what i suggest:
intense fwai 200
custom fabbed headers(i don't think anyone makes em for your ride i could be wrong check intense) 800
smaller pulley 50(puller included)
pay for a tune(300+)
thats like lvl one. obviously you could go different ways about it but headers intake and tune are the big 3.
you'll gain probably 30-40hp at the wheels for around 1500. assuming you can install if yourself.
anything more and your talking dropping a boat load of cash and the more power you make the trannies shat themselves all over the place. also the only good diffs were made by quaife who doesn't sell them anymore. so you're stuck using a clutch based diff which is sadly all you can use.
go google intense 3800. they are basically #1 in engine mods. there website should be all the help you need. or give them a call they are VERY friendly on the phone. so call em up. tell em what you want. and they will tell you what to buy.
INTENSE-Racing.com: 3800 - Performance Packages
simple. easy. fun.
oh and your ability to squeal a tire says nothing about the power of a car'* engine fwiw.
edit as 1999L36 said. with 1500-2k invested and a GOOD tune you can hit high 14s. you probably run high 15s now and dropping a second for 2k is a pretty good deal. unfortunately the car is rather heavy. a large investment needs to be made to make it 'fast'