Ryan,
Doesn't the speedo based its measurement off the wheels/tires so the size of tires will affect it. But with a different diff ratio your rpm's would just be higher for the same speed and therefore should not affect the speedo reading. Typical error between speedo reading and actual could be 3% easily according to BMW.
-Roberto
Doesn't the speedo based its measurement off the wheels/tires so the size of tires will affect it. But with a different diff ratio your rpm's would just be higher for the same speed and therefore should not affect the speedo reading. Typical error between speedo reading and actual could be 3% easily according to BMW.
-Roberto