i would never take a 300z or any car up to top speed,it gets way too scary and loud for me once i hit 115mph,i would have to be a idiot to take any of those cars up to top speed.i was just curious and wanted to find out wanted to find out how fast it could go.if i got up to 140mph it would propably take me 800-900 feet to stop thats just to damn dangerous for me.sorry about the caps the button is jammed.