Super Charger Pulley Question?
 

I am putting on a Vortech Super Charger system this year and I know that I want to go to an 8 Rib Pulley setup on it. Does that require just a pulley or two to purchase or do you need to change out all of the Pulleys? I know Vortech has a complete system but it's around 900.00 so if I don't have to swap out all of them it would obviously be a lot less expensive. Looking for knowledge from all you Super Charger people. What pulleys need changed out? Do I need to change them all? Thanks.