Okay, let me chime in here. If you're looking to soup up a car, then you shouldn't pick a 3x00 lb beast with a v6 in it.

I had the v6 Grant Am GT with the 3.3 and I loved the car in spite of it shooting thick black smoke out the pipes whenever I got on it. Still, I never even attempted to soup it up. That car is a tank, and its slow, and it'll always be a tank and it'll always be slow. Even if you fabbed up a small block v8 to fit under that hood itd be a tough job to get that heavy ass thing to be quick.

My advice, just say no to mods on the 3x00 lb v6. They're nice cars, and they sound pretty nice in the GT models, but they're not for racing. And no, the Grand Prix isn't for racing either. If you wanna wear the Pontiac logo and be a badass whle doing it, you need a Trans Am or GTO or something.