I have to agree that some speedo`s are alot out but i think mines is as close as possible as when i was really revving mine racing a fireblade my speedo was saying about 158, and i didnt really want to hold it any longer as i felt it didnt have much more.

My car has 17`s 215/40, fresh rebuild with low comp pistons, little head work, nearly new tt stg2 t35, greens , 500 cooler, 20psi of boost


Surely If anything my speedo may be less