The formula to convert kph to mph is mph = 0.621371 x kph. The resulting figure indicates the number of miles traveled by an object in an hour.
Kilometers per hour is a measurement of speed in the metric, or SI, system, a decimalbased system of measurement units. According to the National Institute of Standards and Technology, the United States is one of the few industrial countries that has not completely migrated to the metric system for all its measurements. However, converting between the metric system and older units, such as mph, is simple. Besides using formulas, there are numerous online converters or apps for more convenient calculations.
kph x 0.621 = mph.
http://wiki.answers.com/Q/What_is_the_formula_for_...

1. Multiply the miles figure in an MPH expression by the conversion factor of 1.609344 to obtain the corresponding KPH value. This factor represents the number of kilometers in 1
http://www.ehow.com/how_2306811_convertmphkph.ht...

228 KPH equals 141.67 MPH, you might need to slow down there!
http://www.chacha.com/question/whatis228kphconv...

1 mile = 1.609344 kilometers
http://answers.yahoo.com/question/index?qid=200810...
