question on sohc engine...

whats up people, i have a question on individual throttle body systems. I have a 97 Ex civic and i have a few questions. first of all i would like to know how much hp individual throttle bodies gives u. i would also like to know how much it costs and where i can buy one, a website would be good. and finally i would like to know if anybody has done this and how it worked out... thanks.