what was the differance in the two bosses, was the new boss shorter, so the variator closed more, so the belt would go to the top of the variator, I had to shave 1mm. off both sides of the variator to get the same results,. my belt is 24 mm. wide and the variator was 25.5 wide , now it is 23.5 wide , and the belt go,s to the top of the variator pulley now,. it lowered the RPM by 500 to 1000 rpm at speed ,. my steed is the downtown,. 300i just passed 40,000 km.