250RWHP will not be possible with just bolt ons. For an auto, with bolt ons you are looking at around 195-200 RWHP and for a manual around 203-215 RWHP.
To hit 250RWHP or more, you will need some juice, turbo or sc.
well i dont want to have to deal with bottle re-fills all the time...i want the power to always be there and not be bounded by how much n20 you have left. i dont want a turbo b/c of all the hassle...s/c for me. now which one will i choose? idk.
Vortech makes a good kit, there is a Procharger out there that a couple have, and Explorer Express. Since EE isn't out yet, then I would go Vortech. Though the Powerhouse turbo is the best in my opinion.