BC-Racing 135i/335i "ER Series Double Adjustable" coilover kit

By separating the adjustment for compression (bump) and rebound the ER Series allows you find tune the damping rate, to maximise suspension performance on the race track.

Both the BR & ER Series coilovers include camber adjustable aluminium pillow-ball top mounts. The pillowballs themselves are of Japanese manufacture and their solid nature, eliminates any flex or distortion associated with a standard rubber mount, further improving response and handling.

The external reservoir ER Series coilovers allow BC Racing to increase the oil capacity of the damper unit. The additional oil capacity reduces peak oil temperatures, which decreases variations in damping rates due to changes in the oil viscosity. This reduction in damping rate variations improves suspension performance and vehicle predictability under extreme track conditions.

But have the additional benefit of external reservoirs and the ability to allow the end user to individually adjust and set compression and rebound damping rates.Who says size doesn't matter? For the track enthusiasts, keeping the engine cool means more time on the track and more efficient running temperates. The PWR radiator upgrade gives you up you 30% more efficiency over stock with a thicker core, and added cooling with the bar and fin design.