Hey, Ive decided within the next few weeks im going to see if I cant make my self a UD pulley for my car, Everewhere I read it says its 25% under drive (I presume thats 25% smaller diameter...) so all I need now is to go to a SY, get an old one, copy the dimentions except for the dia, spin some steel or alumninumon a latheand find a belt that fits right.

Does anyone know the size or part number for the smaller belt?

Thanks