[JBones81]

I think this all depends on how you want to use the car. For me, for now, I'm doing the intake for the blower noise, an axle-back for the exhaust sounds, and I've wrapped the car, tinted the windows, and done a few other cosmetic things for the looks. Until I get bored at the 650hp level, I'll enjoy the car like this.

I'm enjoying reading about the other suggested mods though. Seems like flex fuel is the way to go for easy power without huge expense.