R34 Z-Tune isn't technically a production car. and it is by no means the fastest car in the world. Bugatti Veyron and Koenigsegg CCX or even the CCR would eat it alive. Enzo's can outrun em too. R34 Ztune is a great car, don't get me wrong. but its somewhat overrated. however, for the price, its the best performance you can get. i will admit though, if it were an F1 versus the Z-Tune, it would have been more fair, but the F1 would have still beaten it in a straight line. CORNERS, thats a different story.