The L220170709 idler relocation bracket is required to install the 18% balancer pulley.
The Lingenfelter LSA Idler Relocation Bracket is designed for the Cadillac CTS-V 2009-2015, or ZL1 Camaro 2012-2015 to allow the installation of larger diameter supercharger pulley on the harmonic balancer or damper. When installing the 9.55" diameter or larger harmonic balancer pulley the stock idler will not have enough clearance to allow the installation.
The kit includes a black hard coat anodized 6061 billet aluminum bracket & stainless fasteners. The kit is designed to work with the stock idler pulley or can also be used with the Lingenfelter 76 MM, 90 MM or 100 mm idlers. Drivers side or bottom location can only use the 76 mm idler.
Lingenfelter does not suggest the use of smaller 50 MM idlers because of issues we have seen with frequent failures due to bearing over speed.