i think 400ish HP would be a more realistic goal
Built 5.4L
Built 4v Heads/Cams
6 Spd
then when you want to push it, throw in a 100-150shot on top, since the motor will be built for it.
400hp n/a would be a very fun streetcar, and with the nitrous for when youre feeling crazy, would be alot sicker than youre everyday Supercharger setup.