Pontiac ZB-05 Grand Prix 2004-2008 ER Coilover QX50 RWD A conventional shock absorber can

A conventional shock absorber can withstand a 2kg spring rate difference before requiring a revalve

Flow Digressive Piston Technology

Each car is different and it may take some time to dial in your preferred settings

Flawless CNC finish

Swift Springs Standard (Hyperco u2013 Substitute)

Pontiac ZB-05 Grand Prix 2004-2008 ER Coilover QX50 RWD A conventional shock absorber canThe BC Racing ER Series Coilover System is the next evolution in your suspension tuning and vehicle setup needs. The ER Series offers 30 clicks of independently adjustable compression and rebound with remote reservoirs to increase oil capacity and help with faster heat dissipation. Each ER Series Coilover System undergoes the same rigorous testing and development as the coilover series that precede it, with the addition of more extensive real world