BC racing’s ER series offers the same high-quality features of the BR and RM series, as well as additional features that help to enhance performance. In addition to separate rebound and compression damping adjustment, these coilovers also have an external oil reservoir attached to the unit, and this brings a considerable boost to their performance.
External reservoirs are beneficial because of the way the performance of oils is affected by temperature. External reservoirs provide additional oil capacity to the dampers and, because there is more of it, the oil is less affected when the damper unit begins to heat up as a result of friction.
This helps to keep the oil cooler than it otherwise would be, and this helps to ensure that the coilovers are able to maintain high performance levels even during heavy use. Being able to maintain the high performance levels of your coilovers means that your vehicle’s road handling performance will also be enhanced.