Reading and comparing compressor maps: rpm vs. speed
 

How can I convert speed to rpm numbers provided in compressor maps.
Some maps show rpm, some m/sec?
Divide the speed by the comp wheel diameter/circumference of the exducer?
Example: Exducer 55.9mm, speed 460 m/sec. ==> 157,200 rpm?

APR R1 diverter, GIAC PC16, 31lb inj, 20x6x2.75 FMIC, 185 g/s MAF flow, DP 'sport cat, Milltek CB Exh, Podi Boost Gauge, 17" OZ F1 225/45-17, PowerSlot