No offense Punck, but you need to spend some time looking at contour.org before you ask such questions. They have a very comprehensive list of mods available, along with a list of supplier websites, most of which will give you some indication of hp and tq gains to expect, just don't belive the claims. You should factor in a 10 or 20 % ideal conditions factor so if it says you will get 10hp expect to get 7 or 8 in a best case.
Having said that and assuming you are going to stay away from forced induction and no2:
1. tune up stuff (plugs, plugwires, synthetic oil)
2. Intake
3. exhaust (headers, y-pipes, catbacks etc.)
4. electronics
5. further improve the breathing (tb's, porting, polishing, swapping manafolds etc.)
Just remember that an engine is basically an air pump, the more air (or combustible mixture) you can put in and get out the more power you make.
And for the most part, if it fits an svt it fits non svt's as well.
98 SE
BAT Big Brake Kit "C", Throttle Hang Fix, B&M Shifter, Lightly Cracked Secondaries, BAT Euro Handling Kit, 20% tint, Removed Ding Strips, ES Motor Mount Inserts, Borla CatBack, Apexi SAFC, HighTower Rear Brace, BAT 19mm rear bar, MSDS Headers & Y, AFE 20-35008 filter, ClutchMasters Stage 1, Fidanza FlyWheel, SVT T.B.
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svt uppers and lowers,
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