PowerBond Race Serpentine Underdrive SFI 18.1 Harmonic Balancer - 6.770 in OD - Black Powder Coat - Internal Balance - GM LS-Series 2070031 Adjustable Vacuum Advance

Adjustable Vacuum Advance

gear cutting

Standard Pinion To large Rear Bearing

BMR's billet aluminum differential bushings replace the entire OE rubber bushing

Can be cleaned in the sink or even in the washing machine

PowerBond Race Serpentine Underdrive SFI 18.1 Harmonic Balancer - 6.770 in OD - Black Powder Coat - Internal Balance - GM LS-Series 2070031 Adjustable Vacuum AdvanceProduct Description: Harmonic Balancer Race Serpentine Underdrive 6. 770 in OD SFI 18. 1 Steel Black Powder Coat Internal Balance GM LS Series Sold Individually PowerBond produces steel harmonic balancers that are designed to outperform conventional harmonic balancers without the weight penalty of many competitive balancers.