PowerBond™ by DAYCO® Race Performance Balancers are designed with a unique combination of material and castings providing the maximum strength and durability of bonded dampening rubber. Each balancer is dynamically balanced for a smooth operation. Modifying the balancer diameter can alter the performance of the accessories and engine rev speeds that can increase the vehicle's horsepower output. These modifications can also help reduce power loss caused by front drive accessories and prevent over-revving alternators. Note: This modified balancer changes the geometry of the original belt drive. Dayco® recommends this balancer to be serviced by a professional installer.