Product Details
BC Racing ER Series Coilovers for the 2007-2013 BMW 3 Series Convertible/Wagon (Non-M) (E91/E93) 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 3 Series Convertible/Wagon (Non-M) chassis and refined until it balances ride quality with performance — the reason 3 Series Convertible/Wagon (Non-M) coilovers from BC Racing are the best-selling adjustable kits in their segment worldwide.
ER Series kits run a linear twin-piston design in a mono-tube body, with compression and rebound on separate external adjusters. That lets you fine-tune chassis balance corner by corner — stiffer front for turn-in, softer rear for exit grip, whatever the session calls for. BC Racing takes pride in choosing spring rates and damper valving that balance comfort and performance — you never end up with the oversprung, harsh-riding kit some brands ship as their only option. Drivers who want to deviate from the factory setup can order Swift Springs, custom spring rates, and custom valving at checkout; BC will re-valve the dampers to match whatever you specify, a level of customization most brands reserve for their top-tier race kits.
BC Racing has been manufacturing adjustable coilovers since 2004 and is one of the most popular coilover brands in the automotive tuning industry for a reason: competitive pricing, deep customization, proven reliability, and a fully rebuildable damper design that lasts years instead of seasons. These 3 Series Convertible/Wagon (Non-M) coilovers arrive tuned for the 3 Series Convertible/Wagon (Non-M) chassis and ready to bolt in — no break-in period, no guessing at setup. Every kit ships with a 2-year manufacturer warranty, lifetime access to BC service parts (pistons, seals, shafts — no unit replacement required when it's time for a rebuild), and in-house tech support from both BC Racing and the Springrates team.
Features
- 30-level rebound adjustment (top of damper)
- 30-level compression adjustment (external reservoir)
- Mono-tube damper with linear twin-piston design
- Ride height adjustable independent of spring preload
- Upper mount hardware varies by chassis — camber plates, pillowball, or reused OEM mounts. See the Specifications table for what's included on your kit.
- Swift Spring and custom spring rate upgrades available at checkout
- Custom damper valving paired with custom spring rates on request
- Fully rebuildable — replacement parts available from BC for the life of the shock
- 2-year manufacturer warranty against defects
Specifications
| Part Number | I-17-ER |
| Part Name | ER Series Coilovers |
| Vehicle | 2007-2013 BMW 3 Series Convertible/Wagon (Non-M) |
| Drivetrain | RWD |
| Chassis Code | E91/E93 |
| Damping Adjustment | 2-Way (30 levels rebound 30 levels compression) |
| Ride-Height Adjustable | Yes |
| Spring Rate - Front | 8 kg/mm |
| Spring Rate - Rear | 14 kg/mm |
| Spring Size - Front | 62-135-8K |
| Spring Size - Rear | 62-235-14K |
| Swift Springs - Front | 62-127-X |
| Swift Springs - Rear | 62-228-X |
| Camber Plates - Front | Included |
| Camber Plates - Rear | Not Applicable |
| Suspension Design - Front | True Coilover |
| Suspension Design - Rear | True Coilover |
| Notes | The ER Series is not available in Extreme-Low configuration. |
Vehicle Fitment
- 2007 BMW 3 Series Convertible/Wagon (Non-M) RWD (E91/E93)
- 2008 BMW 3 Series Convertible/Wagon (Non-M) RWD (E91/E93)
- 2009 BMW 3 Series Convertible/Wagon (Non-M) RWD (E91/E93)
- 2010 BMW 3 Series Convertible/Wagon (Non-M) RWD (E91/E93)
- 2011 BMW 3 Series Convertible/Wagon (Non-M) RWD (E91/E93)
- 2012 BMW 3 Series Convertible/Wagon (Non-M) RWD (E91/E93)
- 2013 BMW 3 Series Convertible/Wagon (Non-M) RWD (E91/E93)