BC Racing ER Series Coilovers for 2005-2008 Porsche 911 AWD (997.1)BC Racing ER Series Coilovers for the 2005 2008 Porsche 911 (997. 1) put race grade adjustability in reach of the serious track day driver, with independent compression and rebound tuning at every corner. Every kit is extensively tested on the 911 997. 1 chassis and refined until it balances ride quality with performance the reason 911 coilovers from BC Racing are the best selling adjustable kits in their segment worldwide. ER Series kits run a linear