Supercharger is the way to go. Magnuson is great. I have one and they're 50 state emissions legal. Adds about 120hp. As far as bolt ons go, cat back exhaust, high flow cats from Magnaflow (if you're not in CA). Suspension helps handle and hook up better, so Hotchkis is pretty good. Tires are a big weak link with these cars. Those Goodyears flat out suck. Also, he could get a Predator tuner and that'll give him more hp and better throttle response, but if he gets a supercharger it'll come with a predator.