just to clear things up. if anyone knows anything about fluid dynamics. alot of factors come into play when choosing a throttle body size. your intake manifold, port work done,valve job,cams,compression. you want to have a certain level of velocity for your motor to be its most efficent. large throttle body,large intake manifold decreases air speed. disrupts air distribution,turbulence and ultimately atomization. just do some research and make sure all your components work with eachother rather than against eachother.