|
The same deal with my old 911, a bit wider but less tall than stock. measured the circumference of each and found the shorter size was 10% smaller. So, if you are reading 60 on your speedo you are traveling at about 54, 70=63. 80=72, ect. Seems to work, never been tagged.
930 is different. If it feels like 50 MPH, your probably doing 75.
|