It's about 3", doesn't really matter unless you want to make it bigger and reduce boost....
It's about 3", doesn't really matter unless you want to make it bigger and reduce boost. You can't easily make it smaller because the nose cone of the s/c sticks out into the back of the pulley. You can machine off some of the metal on the cone though. Also it's pressed on the shaft so you better know what you are doing to remove it and put it back on securely and lined up. Also, to make things more interesting, MB will not sell you that pulley without a whole new S/C and wholesale it's about $1,800. Hence the reason every tuner made a larger crank pulley than a smaller s/c pulley. But please, let us know what happens, sounds like an exciting project.