I have a 91 900 non turbo 16v. I made my own intake with a tornado fuel saver in it, I just gave it a great tune up and I put some bosch platinum 4 spark plugs in. But I want to do something better. I was thinking about installing a cat-back exhaust system. What do you think I should do thats not that expensive, cause im 17 years old and I dont have a job right now.