i came across this website and found it to be useful. go to the bottom part where u can enter your tyre profile and it will tell you the actual speed you are running.
17" Advan RS replica for sale.
Used less than 1000km on skyline ER34.
Colour: Dark Grey/Silver 98% like new!
Size: Front 17x8, Rear 17x9, 5x114.3 (offset should be +28)
Reason for selling: too many spares...