[Hammer]

While you probably won't see 400hp, I would go for a roots style blower. They're dependable on a near stock setup and have great torque for stoplight "altercations". They sell for around 4 grand and it also gets you a new intake ...

If you positively must have the power at all costs, go procharger with a 3 core intercooler... just be prepared for tuning costs to get the most out of it...