GripTec pullies are the premium upgrade for any supercharger build. Belt slip is a very common issue on supercharged components. Often belt slip is noticed when the system squeals, squeaks or boost falls off. Supercharger systems running 3.4 upper pulleys can see as much as a 1.5 psi gain when adding a Griptec pulley. Call Beefcake Racing 1-855-827-7223 from 9am-10pm EST for the best deals, we are the Forced Induction Specialist.