i need help really bad i need to know how to measure a supercharger pulley? i want to decrease the size of my pulley to create more boost some people tell me to put a string around the inside of the pulley and then divide it by 3.14 and thatd be my size and then other people tell me to measure the top of the pulley and divide it by 3.14 then another person said to just measure from 1 side to the other so please someone help how do you measure a supercharger pulley????????