Best route as a new driver... leave the engine alone for a while. It may suck to have a low power car but stock 240's have plenty of power for beginning drivers. I'd put money into other aspects of the car, mod your suspension, your brakes, buy a real nice set of tires, stuff like that. If you do mods like that you'll definitely notice the performance level of your car shoot up without adding a single horse, plus those things also tend to make the car much safer. When it comes to the engine there are so many options to take with these cars that's it's just not something to jump into, give it time, practice driving, figure out what you really want to do with the car because your taste may change down the road. Find some autocross events or join the SCCA and just have a blast and learn about driving, after a few years of that, you'll know exactly what you want out of the car.