Hello, I am wondering about the different sizes of exhaust, I was planning to get the BTG Duals Cat/Back
http://www.pttuning.com/performanceP...BTG-Duals.html but they are only 2 1/4"....I heard that if you will need a bigger size of exhaust to reach higher hp...if thats so...1)how much hp can these 2 1/4" let out? 2)If you have any better exhaust feel free to put in ur 2 cents