I made some screenshots with HUD this time.
The problem is like this:0-50km/h section,the speedo needle works fine,very accurate.
50-100km/h section,the speedo needle is faster than the actual speed. It's 97km/h ,but the speedo needle points to 100km/h
from 150-200km/h section,the speedo needle is slower than the actual speed.It's 204km/h ,but the needle points to 200km/h.
And in the end the speed is 400km/h ,but the needle does not point to 400 !
So I wonder how to calibrate the speedo needle. Thanks