...the pulley shown is nothing like a One/Cooper pulley or an 'S' pulley so if this is it , it won't fit anyway. This is a good design feature because if it did fit , 'underdrive ' crank pulleys makes the supercharger (
MCS) go slower so you lose power , & the alternator slower so you get a flat battery,and on the One/Cooper the water pump goe's slower too so you overheat & blow up the engine. I'm ordering 10
Best Regards Roland GT Baffooning
