Just got an 04 vrsca about a month ago. Completely stock, and I want to make it louder, without spending a ton of money. What are my options? Do you have to remap and change air filters for all exhausts out there? Are there any slip ons that require no additional parts or installation as far as the engine goes? I am happy with the way the stock exhaust looks, just not the sound..thanks for any help you can give me!